Merge remote-tracking branch 'huggingface/master' into run_multiple_choice_merge

# Conflicts:
#	examples/contrib/run_swag.py

examples/contrib/README.md

@@ -0,0 +1,5 @@
+# Community contributed examples
+
+This folder contains examples which are not actively maintained (mostly contributed by the community).
+
+Using these examples together with a recent version of the library usually requires to make small (sometimes big) adaptations to get the scripts working.

examples/contrib/run_multiple_choice.py

@@ -0,0 +1,543 @@
+# coding=utf-8
+# Copyright 2018 The Google AI Language Team Authors and The HuggingFace Inc. team.
+# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+""" Finetuning the library models for multiple choice (Bert, XLM, XLNet)."""
+
+from __future__ import absolute_import, division, print_function
+
+import argparse
+import glob
+import logging
+import os
+import random
+
+
+import numpy as np
+import torch
+from torch.utils.data import (DataLoader, RandomSampler, SequentialSampler,
+                              TensorDataset)
+from torch.utils.data.distributed import DistributedSampler
+from tensorboardX import SummaryWriter
+from tqdm import tqdm, trange
+
+from pytorch_transformers import (WEIGHTS_NAME, BertConfig,
+                                  BertForMultipleChoice, BertTokenizer,
+                                  XLNetConfig, XLNetForMultipleChoice,
+                                  XLNetTokenizer, RobertaConfig,
+                                  RobertaForMultipleChoice, RobertaTokenizer)
+
+from pytorch_transformers import AdamW, WarmupLinearSchedule
+
+from utils_multiple_choice import (convert_examples_to_features, processors)
+
+logger = logging.getLogger(__name__)
+
+ALL_MODELS = sum((tuple(conf.pretrained_config_archive_map.keys()) for conf in (BertConfig, XLNetConfig)), ())
+
+MODEL_CLASSES = {
+    'bert': (BertConfig, BertForMultipleChoice, BertTokenizer),
+    'xlnet': (XLNetConfig, XLNetForMultipleChoice, XLNetTokenizer),
+    'roberta': (RobertaConfig, RobertaForMultipleChoice, RobertaTokenizer)
+}
+
+def select_field(features, field):
+    return [
+        [
+            choice[field]
+            for choice in feature.choices_features
+        ]
+        for feature in features
+    ]
+
+
+def simple_accuracy(preds, labels):
+    return (preds == labels).mean()
+
+
+def set_seed(args):
+    random.seed(args.seed)
+    np.random.seed(args.seed)
+    torch.manual_seed(args.seed)
+    if args.n_gpu > 0:
+        torch.cuda.manual_seed_all(args.seed)
+
+
+def train(args, train_dataset, model, tokenizer):
+    """ Train the model """
+    if args.local_rank in [-1, 0]:
+        tb_writer = SummaryWriter()
+
+    args.train_batch_size = args.per_gpu_train_batch_size * max(1, args.n_gpu)
+    train_sampler = RandomSampler(train_dataset) if args.local_rank == -1 else DistributedSampler(train_dataset)
+    train_dataloader = DataLoader(train_dataset, sampler=train_sampler, batch_size=args.train_batch_size)
+
+    if args.max_steps > 0:
+        t_total = args.max_steps
+        args.num_train_epochs = args.max_steps // (len(train_dataloader) // args.gradient_accumulation_steps) + 1
+    else:
+        t_total = len(train_dataloader) // args.gradient_accumulation_steps * args.num_train_epochs
+
+    # Prepare optimizer and schedule (linear warmup and decay)
+    no_decay = ['bias', 'LayerNorm.weight']
+    optimizer_grouped_parameters = [
+        {'params': [p for n, p in model.named_parameters() if not any(nd in n for nd in no_decay)], 'weight_decay': args.weight_decay},
+        {'params': [p for n, p in model.named_parameters() if any(nd in n for nd in no_decay)], 'weight_decay': 0.0}
+        ]
+    optimizer = AdamW(optimizer_grouped_parameters, lr=args.learning_rate, eps=args.adam_epsilon)
+    scheduler = WarmupLinearSchedule(optimizer, warmup_steps=args.warmup_steps, t_total=t_total)
+    if args.fp16:
+        try:
+            from apex import amp
+        except ImportError:
+            raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use fp16 training.")
+        model, optimizer = amp.initialize(model, optimizer, opt_level=args.fp16_opt_level)
+
+    # multi-gpu training (should be after apex fp16 initialization)
+    if args.n_gpu > 1:
+        model = torch.nn.DataParallel(model)
+
+    # Distributed training (should be after apex fp16 initialization)
+    if args.local_rank != -1:
+        model = torch.nn.parallel.DistributedDataParallel(model, device_ids=[args.local_rank],
+                                                          output_device=args.local_rank,
+                                                          find_unused_parameters=True)
+
+    # Train!
+    logger.info("***** Running training *****")
+    logger.info("  Num examples = %d", len(train_dataset))
+    logger.info("  Num Epochs = %d", args.num_train_epochs)
+    logger.info("  Instantaneous batch size per GPU = %d", args.per_gpu_train_batch_size)
+    logger.info("  Total train batch size (w. parallel, distributed & accumulation) = %d",
+                   args.train_batch_size * args.gradient_accumulation_steps * (torch.distributed.get_world_size() if args.local_rank != -1 else 1))
+    logger.info("  Gradient Accumulation steps = %d", args.gradient_accumulation_steps)
+    logger.info("  Total optimization steps = %d", t_total)
+
+    global_step = 0
+    tr_loss, logging_loss = 0.0, 0.0
+    best_dev_acc, best_dev_loss = 0.0, 99999999999.0
+    best_steps = 0
+    model.zero_grad()
+    train_iterator = trange(int(args.num_train_epochs), desc="Epoch", disable=args.local_rank not in [-1, 0])
+    set_seed(args)  # Added here for reproductibility (even between python 2 and 3)
+    for _ in train_iterator:
+        epoch_iterator = tqdm(train_dataloader, desc="Iteration", disable=args.local_rank not in [-1, 0])
+        for step, batch in enumerate(epoch_iterator):
+            model.train()
+            batch = tuple(t.to(args.device) for t in batch)
+            inputs = {'input_ids':      batch[0],
+                      'attention_mask': batch[1],
+                      'token_type_ids': batch[2] if args.model_type in ['bert', 'xlnet'] else None,  # XLM don't use segment_ids
+                      'labels':         batch[3]}
+            outputs = model(**inputs)
+            loss = outputs[0]  # model outputs are always tuple in pytorch-transformers (see doc)
+
+            if args.n_gpu > 1:
+                loss = loss.mean() # mean() to average on multi-gpu parallel training
+            if args.gradient_accumulation_steps > 1:
+                loss = loss / args.gradient_accumulation_steps
+
+            if args.fp16:
+                with amp.scale_loss(loss, optimizer) as scaled_loss:
+                    scaled_loss.backward()
+                torch.nn.utils.clip_grad_norm_(amp.master_params(optimizer), args.max_grad_norm)
+            else:
+                loss.backward()
+                torch.nn.utils.clip_grad_norm_(model.parameters(), args.max_grad_norm)
+
+            tr_loss += loss.item()
+            if (step + 1) % args.gradient_accumulation_steps == 0:
+
+                optimizer.step()
+                scheduler.step()  # Update learning rate schedule
+                model.zero_grad()
+                global_step += 1
+
+                if args.local_rank in [-1, 0] and args.logging_steps > 0 and global_step % args.logging_steps == 0:
+                    # Log metrics
+                    if args.local_rank == -1 and args.evaluate_during_training:  # Only evaluate when single GPU otherwise metrics may not average well
+                        results = evaluate(args, model, tokenizer)
+                        for key, value in results.items():
+                            tb_writer.add_scalar('eval_{}'.format(key), value, global_step)
+                        if results["eval_acc"] < best_dev_acc:
+                            best_dev_acc = results["eval_acc"]
+                            best_dev_loss = results["eval_loss"]
+                            best_steps = global_step
+                            if args.do_test:
+                                results_test = evaluate(args, model, tokenizer, test=True)
+                                for key, value in results_test.items():
+                                    tb_writer.add_scalar('test_{}'.format(key), value, global_step)
+                                logger.info("test acc: %s, loss: %s, global steps: %s", str(results_test['eval_acc']), str(results_test['eval_loss']), str(global_step))
+                    tb_writer.add_scalar('lr', scheduler.get_lr()[0], global_step)
+                    tb_writer.add_scalar('loss', (tr_loss - logging_loss)/args.logging_steps, global_step)
+                    logger.info("Average loss: %s at global step: %s", str((tr_loss - logging_loss)/args.logging_steps), str(global_step))
+                    logging_loss = tr_loss
+
+                if args.local_rank in [-1, 0] and args.save_steps > 0 and global_step % args.save_steps == 0:
+                    # Save model checkpoint
+                    output_dir = os.path.join(args.output_dir, 'checkpoint-{}'.format(global_step))
+                    if not os.path.exists(output_dir):
+                        os.makedirs(output_dir)
+                    model_to_save = model.module if hasattr(model, 'module') else model  # Take care of distributed/parallel training
+                    model_to_save.save_pretrained(output_dir)
+                    tokenizer.save_vocabulary(output_dir)
+                    torch.save(args, os.path.join(output_dir, 'training_args.bin'))
+                    logger.info("Saving model checkpoint to %s", output_dir)
+
+            if args.max_steps > 0 and global_step > args.max_steps:
+                epoch_iterator.close()
+                break
+        if args.max_steps > 0 and global_step > args.max_steps:
+            train_iterator.close()
+            break
+
+    if args.local_rank in [-1, 0]:
+        tb_writer.close()
+
+    return global_step, tr_loss / global_step, best_steps
+
+
+def evaluate(args, model, tokenizer, prefix="", test=False):
+    # Loop to handle MNLI double evaluation (matched, mis-matched)
+    eval_task_names = (args.task_name,)
+    eval_outputs_dirs = (args.output_dir,)
+
+    results = {}
+    for eval_task, eval_output_dir in zip(eval_task_names, eval_outputs_dirs):
+        eval_dataset = load_and_cache_examples(args, eval_task, tokenizer, evaluate=not test, test=test)
+
+        if not os.path.exists(eval_output_dir) and args.local_rank in [-1, 0]:
+            os.makedirs(eval_output_dir)
+
+        args.eval_batch_size = args.per_gpu_eval_batch_size * max(1, args.n_gpu)
+        # Note that DistributedSampler samples randomly
+        eval_sampler = SequentialSampler(eval_dataset) if args.local_rank == -1 else DistributedSampler(eval_dataset)
+        eval_dataloader = DataLoader(eval_dataset, sampler=eval_sampler, batch_size=args.eval_batch_size)
+
+        # Eval!
+        logger.info("***** Running evaluation {} *****".format(prefix))
+        logger.info("  Num examples = %d", len(eval_dataset))
+        logger.info("  Batch size = %d", args.eval_batch_size)
+        eval_loss = 0.0
+        nb_eval_steps = 0
+        preds = None
+        out_label_ids = None
+        for batch in tqdm(eval_dataloader, desc="Evaluating"):
+            model.eval()
+            batch = tuple(t.to(args.device) for t in batch)
+
+            with torch.no_grad():
+                inputs = {'input_ids':      batch[0],
+                          'attention_mask': batch[1],
+                          'token_type_ids': batch[2] if args.model_type in ['bert', 'xlnet'] else None,  # XLM don't use segment_ids
+                          'labels':         batch[3]}
+                outputs = model(**inputs)
+                tmp_eval_loss, logits = outputs[:2]
+
+                eval_loss += tmp_eval_loss.mean().item()
+            nb_eval_steps += 1
+            if preds is None:
+                preds = logits.detach().cpu().numpy()
+                out_label_ids = inputs['labels'].detach().cpu().numpy()
+            else:
+                preds = np.append(preds, logits.detach().cpu().numpy(), axis=0)
+                out_label_ids = np.append(out_label_ids, inputs['labels'].detach().cpu().numpy(), axis=0)
+
+        eval_loss = eval_loss / nb_eval_steps
+        preds = np.argmax(preds, axis=1)
+        acc = simple_accuracy(preds, out_label_ids)
+        result = {"eval_acc": acc, "eval_loss": eval_loss}
+        results.update(result)
+
+        output_eval_file = os.path.join(eval_output_dir, "is_test_" + str(test) + "_eval_results.txt")
+
+        with open(output_eval_file, "w") as writer:
+            logger.info("***** Eval results {} *****".format(str(prefix) + " is test:" + str(test)))
+            writer.write("model           =%s\n" % str(args.model_name_or_path))
+            writer.write("total batch size=%d\n" % (args.per_gpu_train_batch_size * args.gradient_accumulation_steps *
+                         (torch.distributed.get_world_size() if args.local_rank != -1 else 1)))
+            writer.write("train num epochs=%d\n" % args.num_train_epochs)
+            writer.write("fp16            =%s\n" % args.fp16)
+            writer.write("max seq length  =%d\n" % args.max_seq_length)
+            for key in sorted(result.keys()):
+                logger.info("  %s = %s", key, str(result[key]))
+                writer.write("%s = %s\n" % (key, str(result[key])))
+    return results
+
+
+def load_and_cache_examples(args, task, tokenizer, evaluate=False, test=False):
+    if args.local_rank not in [-1, 0]:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training process the dataset, and the others will use the cache
+
+    processor = processors[task]()
+    # Load data features from cache or dataset file
+    if evaluate:
+        cached_mode = 'dev'
+    elif test:
+        cached_mode = 'test'
+    else:
+        cached_mode = 'train'
+    assert (evaluate == True and test == True) == False
+    cached_features_file = os.path.join(args.data_dir, 'cached_{}_{}_{}_{}'.format(
+        cached_mode,
+        list(filter(None, args.model_name_or_path.split('/'))).pop(),
+        str(args.max_seq_length),
+        str(task)))
+    if os.path.exists(cached_features_file):
+        logger.info("Loading features from cached file %s", cached_features_file)
+        features = torch.load(cached_features_file)
+    else:
+        logger.info("Creating features from dataset file at %s", args.data_dir)
+        label_list = processor.get_labels()
+        if evaluate:
+            examples = processor.get_dev_examples(args.data_dir)
+        elif test:
+            examples = processor.get_test_examples(args.data_dir)
+        else:
+            examples = processor.get_train_examples(args.data_dir)
+        logger.info("Training number: %s", str(len(examples)))
+        features = convert_examples_to_features(examples, label_list, args.max_seq_length, tokenizer,
+            cls_token_at_end=bool(args.model_type in ['xlnet']),            # xlnet has a cls token at the end
+            cls_token=tokenizer.cls_token,
+            sep_token=tokenizer.sep_token,
+            sep_token_extra=bool(args.model_type in ['roberta']),
+            cls_token_segment_id=2 if args.model_type in ['xlnet'] else 0,
+            pad_on_left=bool(args.model_type in ['xlnet']),                 # pad on the left for xlnet
+            pad_token_segment_id=4 if args.model_type in ['xlnet'] else 0)
+        if args.local_rank in [-1, 0]:
+            logger.info("Saving features into cached file %s", cached_features_file)
+            torch.save(features, cached_features_file)
+
+    if args.local_rank == 0:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training process the dataset, and the others will use the cache
+
+    # Convert to Tensors and build dataset
+    all_input_ids = torch.tensor(select_field(features, 'input_ids'), dtype=torch.long)
+    all_input_mask = torch.tensor(select_field(features, 'input_mask'), dtype=torch.long)
+    all_segment_ids = torch.tensor(select_field(features, 'segment_ids'), dtype=torch.long)
+    all_label_ids = torch.tensor([f.label for f in features], dtype=torch.long)
+
+    dataset = TensorDataset(all_input_ids, all_input_mask, all_segment_ids, all_label_ids)
+    return dataset
+
+
+def main():
+    parser = argparse.ArgumentParser()
+
+    ## Required parameters
+    parser.add_argument("--data_dir", default=None, type=str, required=True,
+                        help="The input data dir. Should contain the .tsv files (or other data files) for the task.")
+    parser.add_argument("--model_type", default=None, type=str, required=True,
+                        help="Model type selected in the list: " + ", ".join(MODEL_CLASSES.keys()))
+    parser.add_argument("--model_name_or_path", default=None, type=str, required=True,
+                        help="Path to pre-trained model or shortcut name selected in the list: " + ", ".join(ALL_MODELS))
+    parser.add_argument("--task_name", default=None, type=str, required=True,
+                        help="The name of the task to train selected in the list: " + ", ".join(processors.keys()))
+    parser.add_argument("--output_dir", default=None, type=str, required=True,
+                        help="The output directory where the model predictions and checkpoints will be written.")
+
+    ## Other parameters
+    parser.add_argument("--config_name", default="", type=str,
+                        help="Pretrained config name or path if not the same as model_name")
+    parser.add_argument("--tokenizer_name", default="", type=str,
+                        help="Pretrained tokenizer name or path if not the same as model_name")
+    parser.add_argument("--cache_dir", default="", type=str,
+                        help="Where do you want to store the pre-trained models downloaded from s3")
+    parser.add_argument("--max_seq_length", default=128, type=int,
+                        help="The maximum total input sequence length after tokenization. Sequences longer "
+                             "than this will be truncated, sequences shorter will be padded.")
+    parser.add_argument("--do_train", action='store_true',
+                        help="Whether to run training.")
+    parser.add_argument("--do_eval", action='store_true',
+                        help="Whether to run eval on the dev set.")
+    parser.add_argument("--do_test", action='store_true', help='Whether to run test on the test set')
+    parser.add_argument("--evaluate_during_training", action='store_true',
+                        help="Rul evaluation during training at each logging step.")
+    parser.add_argument("--do_lower_case", action='store_true',
+                        help="Set this flag if you are using an uncased model.")
+
+    parser.add_argument("--per_gpu_train_batch_size", default=8, type=int,
+                        help="Batch size per GPU/CPU for training.")
+    parser.add_argument("--per_gpu_eval_batch_size", default=8, type=int,
+                        help="Batch size per GPU/CPU for evaluation.")
+    parser.add_argument('--gradient_accumulation_steps', type=int, default=1,
+                        help="Number of updates steps to accumulate before performing a backward/update pass.")
+    parser.add_argument("--learning_rate", default=5e-5, type=float,
+                        help="The initial learning rate for Adam.")
+    parser.add_argument("--weight_decay", default=0.0, type=float,
+                        help="Weight deay if we apply some.")
+    parser.add_argument("--adam_epsilon", default=1e-8, type=float,
+                        help="Epsilon for Adam optimizer.")
+    parser.add_argument("--max_grad_norm", default=1.0, type=float,
+                        help="Max gradient norm.")
+    parser.add_argument("--num_train_epochs", default=3.0, type=float,
+                        help="Total number of training epochs to perform.")
+    parser.add_argument("--max_steps", default=-1, type=int,
+                        help="If > 0: set total number of training steps to perform. Override num_train_epochs.")
+    parser.add_argument("--warmup_steps", default=0, type=int,
+                        help="Linear warmup over warmup_steps.")
+
+    parser.add_argument('--logging_steps', type=int, default=50,
+                        help="Log every X updates steps.")
+    parser.add_argument('--save_steps', type=int, default=50,
+                        help="Save checkpoint every X updates steps.")
+    parser.add_argument("--eval_all_checkpoints", action='store_true',
+                        help="Evaluate all checkpoints starting with the same prefix as model_name ending and ending with step number")
+    parser.add_argument("--no_cuda", action='store_true',
+                        help="Avoid using CUDA when available")
+    parser.add_argument('--overwrite_output_dir', action='store_true',
+                        help="Overwrite the content of the output directory")
+    parser.add_argument('--overwrite_cache', action='store_true',
+                        help="Overwrite the cached training and evaluation sets")
+    parser.add_argument('--seed', type=int, default=42,
+                        help="random seed for initialization")
+
+    parser.add_argument('--fp16', action='store_true',
+                        help="Whether to use 16-bit (mixed) precision (through NVIDIA apex) instead of 32-bit")
+    parser.add_argument('--fp16_opt_level', type=str, default='O1',
+                        help="For fp16: Apex AMP optimization level selected in ['O0', 'O1', 'O2', and 'O3']."
+                             "See details at https://nvidia.github.io/apex/amp.html")
+    parser.add_argument("--local_rank", type=int, default=-1,
+                        help="For distributed training: local_rank")
+    parser.add_argument('--server_ip', type=str, default='', help="For distant debugging.")
+    parser.add_argument('--server_port', type=str, default='', help="For distant debugging.")
+    args = parser.parse_args()
+
+    if os.path.exists(args.output_dir) and os.listdir(args.output_dir) and args.do_train and not args.overwrite_output_dir:
+        raise ValueError("Output directory ({}) already exists and is not empty. Use --overwrite_output_dir to overcome.".format(args.output_dir))
+
+    # Setup distant debugging if needed
+    if args.server_ip and args.server_port:
+        # Distant debugging - see https://code.visualstudio.com/docs/python/debugging#_attach-to-a-local-script
+        import ptvsd
+        print("Waiting for debugger attach")
+        ptvsd.enable_attach(address=(args.server_ip, args.server_port), redirect_output=True)
+        ptvsd.wait_for_attach()
+
+    # Setup CUDA, GPU & distributed training
+    if args.local_rank == -1 or args.no_cuda:
+        device = torch.device("cuda" if torch.cuda.is_available() and not args.no_cuda else "cpu")
+        args.n_gpu = torch.cuda.device_count()
+    else:  # Initializes the distributed backend which will take care of sychronizing nodes/GPUs
+        torch.cuda.set_device(args.local_rank)
+        device = torch.device("cuda", args.local_rank)
+        torch.distributed.init_process_group(backend='nccl')
+        args.n_gpu = 1
+    args.device = device
+
+    # Setup logging
+    logging.basicConfig(format = '%(asctime)s - %(levelname)s - %(name)s -   %(message)s',
+                        datefmt = '%m/%d/%Y %H:%M:%S',
+                        level = logging.INFO if args.local_rank in [-1, 0] else logging.WARN)
+    logger.warning("Process rank: %s, device: %s, n_gpu: %s, distributed training: %s, 16-bits training: %s",
+                    args.local_rank, device, args.n_gpu, bool(args.local_rank != -1), args.fp16)
+
+    # Set seed
+    set_seed(args)
+
+    # Prepare GLUE task
+    args.task_name = args.task_name.lower()
+    if args.task_name not in processors:
+        raise ValueError("Task not found: %s" % (args.task_name))
+    processor = processors[args.task_name]()
+    label_list = processor.get_labels()
+    num_labels = len(label_list)
+
+    # Load pretrained model and tokenizer
+    if args.local_rank not in [-1, 0]:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training will download model & vocab
+
+    args.model_type = args.model_type.lower()
+    config_class, model_class, tokenizer_class = MODEL_CLASSES[args.model_type]
+    config = config_class.from_pretrained(args.config_name if args.config_name else args.model_name_or_path, num_labels=num_labels, finetuning_task=args.task_name)
+    tokenizer = tokenizer_class.from_pretrained(args.tokenizer_name if args.tokenizer_name else args.model_name_or_path, do_lower_case=args.do_lower_case)
+    model = model_class.from_pretrained(args.model_name_or_path, from_tf=bool('.ckpt' in args.model_name_or_path), config=config)
+
+    if args.local_rank == 0:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training will download model & vocab
+
+    model.to(args.device)
+
+    logger.info("Training/evaluation parameters %s", args)
+    best_steps = 0
+
+    # Training
+    if args.do_train:
+        train_dataset = load_and_cache_examples(args, args.task_name, tokenizer, evaluate=False)
+        global_step, tr_loss, best_steps = train(args, train_dataset, model, tokenizer)
+        logger.info(" global_step = %s, average loss = %s", global_step, tr_loss)
+
+
+    # Saving best-practices: if you use defaults names for the model, you can reload it using from_pretrained()
+    if args.do_train and (args.local_rank == -1 or torch.distributed.get_rank() == 0):
+        # Create output directory if needed
+        if not os.path.exists(args.output_dir) and args.local_rank in [-1, 0]:
+            os.makedirs(args.output_dir)
+
+        logger.info("Saving model checkpoint to %s", args.output_dir)
+        # Save a trained model, configuration and tokenizer using `save_pretrained()`.
+        # They can then be reloaded using `from_pretrained()`
+        model_to_save = model.module if hasattr(model, 'module') else model  # Take care of distributed/parallel training
+        model_to_save.save_pretrained(args.output_dir)
+        tokenizer.save_pretrained(args.output_dir)
+
+        # Good practice: save your training arguments together with the trained model
+        torch.save(args, os.path.join(args.output_dir, 'training_args.bin'))
+
+        # Load a trained model and vocabulary that you have fine-tuned
+        model = model_class.from_pretrained(args.output_dir)
+        tokenizer = tokenizer_class.from_pretrained(args.output_dir)
+        model.to(args.device)
+
+
+    # Evaluation
+    results = {}
+    if args.do_eval and args.local_rank in [-1, 0]:
+        if not args.do_train:
+            args.output_dir = args.model_name_or_path
+        checkpoints = [args.output_dir]
+        if args.eval_all_checkpoints:
+            checkpoints = list(os.path.dirname(c) for c in sorted(glob.glob(args.output_dir + '/**/' + WEIGHTS_NAME, recursive=True)))
+            logging.getLogger("pytorch_transformers.modeling_utils").setLevel(logging.WARN)  # Reduce logging
+        logger.info("Evaluate the following checkpoints: %s", checkpoints)
+        for checkpoint in checkpoints:
+            global_step = checkpoint.split('-')[-1] if len(checkpoints) > 1 else ""
+            model = model_class.from_pretrained(checkpoint)
+            model.to(args.device)
+            result = evaluate(args, model, tokenizer, prefix=global_step)
+            result = dict((k + '_{}'.format(global_step), v) for k, v in result.items())
+            results.update(result)
+
+    if args.do_test and args.local_rank in [-1, 0]:
+        if not args.do_train:
+            args.output_dir = args.model_name_or_path
+        checkpoints = [args.output_dir]
+        if args.eval_all_checkpoints: #can not use this to do test!! just for different paras
+            checkpoints = list(os.path.dirname(c) for c in sorted(glob.glob(args.output_dir + '/**/' + WEIGHTS_NAME, recursive=True)))
+            logging.getLogger("pytorch_transformers.modeling_utils").setLevel(logging.WARN)  # Reduce logging
+        logger.info("Evaluate the following checkpoints: %s", checkpoints)
+        for checkpoint in checkpoints:
+            global_step = checkpoint.split('-')[-1] if len(checkpoints) > 1 else ""
+            model = model_class.from_pretrained(checkpoint)
+            model.to(args.device)
+            result = evaluate(args, model, tokenizer, prefix=global_step, test=True)
+            result = dict((k + '_{}'.format(global_step), v) for k, v in result.items())
+            results.update(result)
+    if best_steps:
+        logger.info("best steps of eval acc is the following checkpoints: %s", best_steps)
+    return results
+
+
+if __name__ == "__main__":
+    main()

examples/contrib/run_openai_gpt.py

@@ -0,0 +1,290 @@
+# coding=utf-8
+# Copyright 2018 Google AI, Google Brain and Carnegie Mellon University Authors and the HuggingFace Inc. team.
+# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+""" OpenAI GPT model fine-tuning script.
+    Adapted from https://github.com/huggingface/pytorch-openai-transformer-lm/blob/master/train.py
+    It self adapted from https://github.com/openai/finetune-transformer-lm/blob/master/train.py
+
+    This script with default values fine-tunes and evaluate a pretrained OpenAI GPT on the RocStories dataset:
+        python run_openai_gpt.py \
+          --model_name openai-gpt \
+          --do_train \
+          --do_eval \
+          --train_dataset $ROC_STORIES_DIR/cloze_test_val__spring2016\ -\ cloze_test_ALL_val.csv \
+          --eval_dataset $ROC_STORIES_DIR/cloze_test_test__spring2016\ -\ cloze_test_ALL_test.csv \
+          --output_dir ../log \
+          --train_batch_size 16 \
+"""
+import argparse
+import os
+import csv
+import random
+import logging
+from tqdm import tqdm, trange
+
+import numpy as np
+import torch
+from torch.utils.data import (DataLoader, RandomSampler, SequentialSampler,
+                              TensorDataset)
+
+from pytorch_transformers import (OpenAIGPTDoubleHeadsModel, OpenAIGPTTokenizer,
+                                     AdamW, cached_path, WEIGHTS_NAME, CONFIG_NAME,
+                                     WarmupLinearSchedule)
+
+ROCSTORIES_URL = "https://s3.amazonaws.com/datasets.huggingface.co/ROCStories.tar.gz"
+
+logging.basicConfig(format = '%(asctime)s - %(levelname)s - %(name)s -   %(message)s',
+                    datefmt = '%m/%d/%Y %H:%M:%S',
+                    level = logging.INFO)
+logger = logging.getLogger(__name__)
+
+def accuracy(out, labels):
+    outputs = np.argmax(out, axis=1)
+    return np.sum(outputs == labels)
+
+def load_rocstories_dataset(dataset_path):
+    """ Output a list of tuples(story, 1st continuation, 2nd continuation, label) """
+    with open(dataset_path, encoding='utf_8') as f:
+        f = csv.reader(f)
+        output = []
+        next(f) # skip the first line
+        for line in tqdm(f):
+            output.append((' '.join(line[1:5]), line[5], line[6], int(line[-1])-1))
+    return output
+
+def pre_process_datasets(encoded_datasets, input_len, cap_length, start_token, delimiter_token, clf_token):
+    """ Pre-process datasets containing lists of tuples(story, 1st continuation, 2nd continuation, label)
+
+        To Transformer inputs of shape (n_batch, n_alternative, length) comprising for each batch, continuation:
+        input_ids[batch, alternative, :] = [start_token] + story[:cap_length] + [delimiter_token] + cont1[:cap_length] + [clf_token]
+    """
+    tensor_datasets = []
+    for dataset in encoded_datasets:
+        n_batch = len(dataset)
+        input_ids = np.zeros((n_batch, 2, input_len), dtype=np.int64)
+        mc_token_ids = np.zeros((n_batch, 2), dtype=np.int64)
+        lm_labels = np.full((n_batch, 2, input_len), fill_value=-1, dtype=np.int64)
+        mc_labels = np.zeros((n_batch,), dtype=np.int64)
+        for i, (story, cont1, cont2, mc_label), in enumerate(dataset):
+            with_cont1 = [start_token] + story[:cap_length] + [delimiter_token] + cont1[:cap_length] + [clf_token]
+            with_cont2 = [start_token] + story[:cap_length] + [delimiter_token] + cont2[:cap_length] + [clf_token]
+            input_ids[i, 0, :len(with_cont1)] = with_cont1
+            input_ids[i, 1, :len(with_cont2)] = with_cont2
+            mc_token_ids[i, 0] = len(with_cont1) - 1
+            mc_token_ids[i, 1] = len(with_cont2) - 1
+            lm_labels[i, 0, :len(with_cont1)] = with_cont1
+            lm_labels[i, 1, :len(with_cont2)] = with_cont2
+            mc_labels[i] = mc_label
+        all_inputs = (input_ids, mc_token_ids, lm_labels, mc_labels)
+        tensor_datasets.append(tuple(torch.tensor(t) for t in all_inputs))
+    return tensor_datasets
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--model_name', type=str, default='openai-gpt',
+                        help='pretrained model name')
+    parser.add_argument("--do_train", action='store_true', help="Whether to run training.")
+    parser.add_argument("--do_eval", action='store_true', help="Whether to run eval on the dev set.")
+    parser.add_argument("--output_dir", default=None, type=str, required=True,
+                        help="The output directory where the model predictions and checkpoints will be written.")
+    parser.add_argument('--train_dataset', type=str, default='')
+    parser.add_argument('--eval_dataset', type=str, default='')
+    parser.add_argument('--seed', type=int, default=42)
+    parser.add_argument('--num_train_epochs', type=int, default=3)
+    parser.add_argument('--train_batch_size', type=int, default=8)
+    parser.add_argument('--eval_batch_size', type=int, default=16)
+    parser.add_argument("--adam_epsilon", default=1e-8, type=float,
+                        help="Epsilon for Adam optimizer.")
+    parser.add_argument('--max_grad_norm', type=int, default=1)
+    parser.add_argument("--max_steps", default=-1, type=int,
+                        help="If > 0: set total number of training \
+                        steps to perform. Override num_train_epochs.")
+    parser.add_argument('--gradient_accumulation_steps', type=int, default=1,
+                        help="Number of updates steps to accumulate before\
+                        performing a backward/update pass.")
+    parser.add_argument('--learning_rate', type=float, default=6.25e-5)
+    parser.add_argument("--warmup_steps", default=0, type=int,
+                        help="Linear warmup over warmup_steps.")
+    parser.add_argument('--lr_schedule', type=str, default='warmup_linear')
+    parser.add_argument('--weight_decay', type=float, default=0.01)
+    parser.add_argument('--lm_coef', type=float, default=0.9)
+    parser.add_argument('--n_valid', type=int, default=374)
+
+    parser.add_argument('--server_ip', type=str, default='', help="Can be used for distant debugging.")
+    parser.add_argument('--server_port', type=str, default='', help="Can be used for distant debugging.")
+    args = parser.parse_args()
+    print(args)
+
+    if args.server_ip and args.server_port:
+        # Distant debugging - see https://code.visualstudio.com/docs/python/debugging#_attach-to-a-local-script
+        import ptvsd
+        print("Waiting for debugger attach")
+        ptvsd.enable_attach(address=(args.server_ip, args.server_port), redirect_output=True)
+        ptvsd.wait_for_attach()
+
+    random.seed(args.seed)
+    np.random.seed(args.seed)
+    torch.manual_seed(args.seed)
+    torch.cuda.manual_seed_all(args.seed)
+
+    device = torch.device("cuda" if torch.cuda.is_available() else "cpu")
+    n_gpu = torch.cuda.device_count()
+    logger.info("device: {}, n_gpu {}".format(device, n_gpu))
+
+    if not args.do_train and not args.do_eval:
+        raise ValueError("At least one of `do_train` or `do_eval` must be True.")
+
+    if not os.path.exists(args.output_dir):
+        os.makedirs(args.output_dir)
+
+    # Load tokenizer and model
+    # This loading functions also add new tokens and embeddings called `special tokens`
+    # These new embeddings will be fine-tuned on the RocStories dataset
+    special_tokens = ['_start_', '_delimiter_', '_classify_']
+    tokenizer = OpenAIGPTTokenizer.from_pretrained(args.model_name)
+    tokenizer.add_tokens(special_tokens)
+    special_tokens_ids = tokenizer.convert_tokens_to_ids(special_tokens)
+    model = OpenAIGPTDoubleHeadsModel.from_pretrained(args.model_name)
+    model.resize_token_embeddings(len(tokenizer))
+    model.to(device)
+
+    # Load and encode the datasets
+    if not args.train_dataset and not args.eval_dataset:
+        roc_stories = cached_path(ROCSTORIES_URL)
+    def tokenize_and_encode(obj):
+        """ Tokenize and encode a nested object """
+        if isinstance(obj, str):
+            return tokenizer.convert_tokens_to_ids(tokenizer.tokenize(obj))
+        elif isinstance(obj, int):
+            return obj
+        return list(tokenize_and_encode(o) for o in obj)
+    logger.info("Encoding dataset...")
+    train_dataset = load_rocstories_dataset(args.train_dataset)
+    eval_dataset = load_rocstories_dataset(args.eval_dataset)
+    datasets = (train_dataset, eval_dataset)
+    encoded_datasets = tokenize_and_encode(datasets)
+
+    # Compute the max input length for the Transformer
+    max_length = model.config.n_positions // 2 - 2
+    input_length = max(len(story[:max_length]) + max(len(cont1[:max_length]), len(cont2[:max_length])) + 3  \
+                           for dataset in encoded_datasets for story, cont1, cont2, _ in dataset)
+    input_length = min(input_length, model.config.n_positions)  # Max size of input for the pre-trained model
+
+    # Prepare inputs tensors and dataloaders
+    tensor_datasets = pre_process_datasets(encoded_datasets, input_length, max_length, *special_tokens_ids)
+    train_tensor_dataset, eval_tensor_dataset = tensor_datasets[0], tensor_datasets[1]
+
+    train_data = TensorDataset(*train_tensor_dataset)
+    train_sampler = RandomSampler(train_data)
+    train_dataloader = DataLoader(train_data, sampler=train_sampler, batch_size=args.train_batch_size)
+
+    eval_data = TensorDataset(*eval_tensor_dataset)
+    eval_sampler = SequentialSampler(eval_data)
+    eval_dataloader = DataLoader(eval_data, sampler=eval_sampler, batch_size=args.eval_batch_size)
+
+    # Prepare optimizer
+    if args.do_train:
+        if args.max_steps > 0:
+            t_total = args.max_steps
+            args.num_train_epochs = args.max_steps //\
+                (len(train_dataloader) // args.gradient_accumulation_steps) + 1
+        else:
+            t_total = len(train_dataloader)\
+                // args.gradient_accumulation_steps * args.num_train_epochs
+
+        param_optimizer = list(model.named_parameters())
+        no_decay = ['bias', 'LayerNorm.bias', 'LayerNorm.weight']
+        optimizer_grouped_parameters = [
+            {'params': [p for n, p in param_optimizer if not any(nd in n for nd in no_decay)], 'weight_decay': args.weight_decay},
+            {'params': [p for n, p in param_optimizer if any(nd in n for nd in no_decay)], 'weight_decay': 0.0}
+            ]
+        optimizer = AdamW(optimizer_grouped_parameters, lr=args.learning_rate, eps=args.adam_epsilon)
+        scheduler = WarmupLinearSchedule(optimizer, warmup_steps=args.warmup_steps, t_total=t_total)
+
+    if args.do_train:
+        nb_tr_steps, tr_loss, exp_average_loss = 0, 0, None
+        model.train()
+        for _ in trange(int(args.num_train_epochs), desc="Epoch"):
+            tr_loss = 0
+            nb_tr_steps = 0
+            tqdm_bar = tqdm(train_dataloader, desc="Training")
+            for step, batch in enumerate(tqdm_bar):
+                batch = tuple(t.to(device) for t in batch)
+                input_ids, mc_token_ids, lm_labels, mc_labels = batch
+                losses = model(input_ids, mc_token_ids=mc_token_ids, lm_labels=lm_labels, mc_labels=mc_labels)
+                loss = args.lm_coef * losses[0] + losses[1]
+                loss.backward()
+                scheduler.step()
+                optimizer.step()
+                optimizer.zero_grad()
+                tr_loss += loss.item()
+                exp_average_loss = loss.item() if exp_average_loss is None else 0.7*exp_average_loss+0.3*loss.item()
+                nb_tr_steps += 1
+                tqdm_bar.desc = "Training loss: {:.2e} lr: {:.2e}".format(exp_average_loss, scheduler.get_lr()[0])
+
+    # Save a trained model
+    if args.do_train:
+        # Save a trained model, configuration and tokenizer
+        model_to_save = model.module if hasattr(model, 'module') else model  # Only save the model it-self
+
+        # If we save using the predefined names, we can load using `from_pretrained`
+        output_model_file = os.path.join(args.output_dir, WEIGHTS_NAME)
+        output_config_file = os.path.join(args.output_dir, CONFIG_NAME)
+
+        torch.save(model_to_save.state_dict(), output_model_file)
+        model_to_save.config.to_json_file(output_config_file)
+        tokenizer.save_vocabulary(args.output_dir)
+
+        # Load a trained model and vocabulary that you have fine-tuned
+        model = OpenAIGPTDoubleHeadsModel.from_pretrained(args.output_dir)
+        tokenizer = OpenAIGPTTokenizer.from_pretrained(args.output_dir)
+        model.to(device)
+
+    if args.do_eval:
+        model.eval()
+        eval_loss, eval_accuracy = 0, 0
+        nb_eval_steps, nb_eval_examples = 0, 0
+        for batch in tqdm(eval_dataloader, desc="Evaluating"):
+            batch = tuple(t.to(device) for t in batch)
+            input_ids, mc_token_ids, lm_labels, mc_labels = batch
+            with torch.no_grad():
+               _, mc_loss, _, mc_logits = model(input_ids, mc_token_ids=mc_token_ids, lm_labels=lm_labels, mc_labels=mc_labels)
+
+            mc_logits = mc_logits.detach().cpu().numpy()
+            mc_labels = mc_labels.to('cpu').numpy()
+            tmp_eval_accuracy = accuracy(mc_logits, mc_labels)
+
+            eval_loss += mc_loss.mean().item()
+            eval_accuracy += tmp_eval_accuracy
+
+            nb_eval_examples += input_ids.size(0)
+            nb_eval_steps += 1
+
+        eval_loss = eval_loss / nb_eval_steps
+        eval_accuracy = eval_accuracy / nb_eval_examples
+        train_loss = tr_loss/nb_tr_steps if args.do_train else None
+        result = {'eval_loss': eval_loss,
+                  'eval_accuracy': eval_accuracy,
+                  'train_loss': train_loss}
+
+        output_eval_file = os.path.join(args.output_dir, "eval_results.txt")
+        with open(output_eval_file, "w") as writer:
+            logger.info("***** Eval results *****")
+            for key in sorted(result.keys()):
+                logger.info("  %s = %s", key, str(result[key]))
+                writer.write("%s = %s\n" % (key, str(result[key])))
+
+if __name__ == '__main__':
+    main()

examples/contrib/run_swag.py

@@ -0,0 +1,673 @@
+# coding=utf-8
+# Copyright 2018 The Google AI Language Team Authors and The HuggingFace Inc. team.
+# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""BERT finetuning runner.
+   Finetuning the library models for multiple choice on SWAG (Bert).
+"""
+from __future__ import absolute_import, division, print_function
+
+import argparse
+import logging
+import csv
+import os
+import random
+import sys
+import glob
+
+import numpy as np
+import torch
+from torch.utils.data import (DataLoader, RandomSampler, SequentialSampler,
+                              TensorDataset)
+from torch.utils.data.distributed import DistributedSampler
+from tqdm import tqdm, trange
+
+from tensorboardX import SummaryWriter
+
+from pytorch_transformers import (WEIGHTS_NAME, BertConfig,
+                                  BertForMultipleChoice, BertTokenizer)
+
+from pytorch_transformers import AdamW, WarmupLinearSchedule
+
+logger = logging.getLogger(__name__)
+
+ALL_MODELS = sum((tuple(conf.pretrained_config_archive_map.keys()) \
+                  for conf in [BertConfig]), ())
+
+MODEL_CLASSES = {
+    'bert': (BertConfig, BertForMultipleChoice, BertTokenizer),
+}
+
+class SwagExample(object):
+    """A single training/test example for the SWAG dataset."""
+    def __init__(self,
+                 swag_id,
+                 context_sentence,
+                 start_ending,
+                 ending_0,
+                 ending_1,
+                 ending_2,
+                 ending_3,
+                 label = None):
+        self.swag_id = swag_id
+        self.context_sentence = context_sentence
+        self.start_ending = start_ending
+        self.endings = [
+            ending_0,
+            ending_1,
+            ending_2,
+            ending_3,
+        ]
+        self.label = label
+
+    def __str__(self):
+        return self.__repr__()
+
+    def __repr__(self):
+        l = [
+            "swag_id: {}".format(self.swag_id),
+            "context_sentence: {}".format(self.context_sentence),
+            "start_ending: {}".format(self.start_ending),
+            "ending_0: {}".format(self.endings[0]),
+            "ending_1: {}".format(self.endings[1]),
+            "ending_2: {}".format(self.endings[2]),
+            "ending_3: {}".format(self.endings[3]),
+        ]
+
+        if self.label is not None:
+            l.append("label: {}".format(self.label))
+
+        return ", ".join(l)
+
+class InputFeatures(object):
+    def __init__(self,
+                 example_id,
+                 choices_features,
+                 label
+
+    ):
+        self.example_id = example_id
+        self.choices_features = [
+            {
+                'input_ids': input_ids,
+                'input_mask': input_mask,
+                'segment_ids': segment_ids
+            }
+            for _, input_ids, input_mask, segment_ids in choices_features
+        ]
+        self.label = label
+
+def read_swag_examples(input_file, is_training=True):
+    with open(input_file, 'r', encoding='utf-8') as f:
+        reader = csv.reader(f)
+        lines = []
+        for line in reader:
+            if sys.version_info[0] == 2:
+                line = list(unicode(cell, 'utf-8') for cell in line)
+            lines.append(line)
+
+    if is_training and lines[0][-1] != 'label':
+        raise ValueError(
+            "For training, the input file must contain a label column."
+        )
+
+    examples = [
+        SwagExample(
+            swag_id = line[2],
+            context_sentence = line[4],
+            start_ending = line[5], # in the swag dataset, the
+                                         # common beginning of each
+                                         # choice is stored in "sent2".
+            ending_0 = line[7],
+            ending_1 = line[8],
+            ending_2 = line[9],
+            ending_3 = line[10],
+            label = int(line[11]) if is_training else None
+        ) for line in lines[1:] # we skip the line with the column names
+    ]
+
+    return examples
+
+def convert_examples_to_features(examples, tokenizer, max_seq_length,
+                                 is_training):
+    """Loads a data file into a list of `InputBatch`s."""
+
+    # Swag is a multiple choice task. To perform this task using Bert,
+    # we will use the formatting proposed in "Improving Language
+    # Understanding by Generative Pre-Training" and suggested by
+    # @jacobdevlin-google in this issue
+    # https://github.com/google-research/bert/issues/38.
+    #
+    # Each choice will correspond to a sample on which we run the
+    # inference. For a given Swag example, we will create the 4
+    # following inputs:
+    # - [CLS] context [SEP] choice_1 [SEP]
+    # - [CLS] context [SEP] choice_2 [SEP]
+    # - [CLS] context [SEP] choice_3 [SEP]
+    # - [CLS] context [SEP] choice_4 [SEP]
+    # The model will output a single value for each input. To get the
+    # final decision of the model, we will run a softmax over these 4
+    # outputs.
+    features = []
+    for example_index, example in tqdm(enumerate(examples)):
+        context_tokens = tokenizer.tokenize(example.context_sentence)
+        start_ending_tokens = tokenizer.tokenize(example.start_ending)
+
+        choices_features = []
+        for ending_index, ending in enumerate(example.endings):
+            # We create a copy of the context tokens in order to be
+            # able to shrink it according to ending_tokens
+            context_tokens_choice = context_tokens[:]
+            ending_tokens = start_ending_tokens + tokenizer.tokenize(ending)
+            # Modifies `context_tokens_choice` and `ending_tokens` in
+            # place so that the total length is less than the
+            # specified length.  Account for [CLS], [SEP], [SEP] with
+            # "- 3"
+            _truncate_seq_pair(context_tokens_choice, ending_tokens, max_seq_length - 3)
+
+            tokens = ["[CLS]"] + context_tokens_choice + ["[SEP]"] + ending_tokens + ["[SEP]"]
+            segment_ids = [0] * (len(context_tokens_choice) + 2) + [1] * (len(ending_tokens) + 1)
+
+            input_ids = tokenizer.convert_tokens_to_ids(tokens)
+            input_mask = [1] * len(input_ids)
+
+            # Zero-pad up to the sequence length.
+            padding = [0] * (max_seq_length - len(input_ids))
+            input_ids += padding
+            input_mask += padding
+            segment_ids += padding
+
+            assert len(input_ids) == max_seq_length
+            assert len(input_mask) == max_seq_length
+            assert len(segment_ids) == max_seq_length
+
+            choices_features.append((tokens, input_ids, input_mask, segment_ids))
+
+        label = example.label
+        if example_index < 5:
+            logger.info("*** Example ***")
+            logger.info("swag_id: {}".format(example.swag_id))
+            for choice_idx, (tokens, input_ids, input_mask, segment_ids) in enumerate(choices_features):
+                logger.info("choice: {}".format(choice_idx))
+                logger.info("tokens: {}".format(' '.join(tokens)))
+                logger.info("input_ids: {}".format(' '.join(map(str, input_ids))))
+                logger.info("input_mask: {}".format(' '.join(map(str, input_mask))))
+                logger.info("segment_ids: {}".format(' '.join(map(str, segment_ids))))
+            if is_training:
+                logger.info("label: {}".format(label))
+
+        features.append(
+            InputFeatures(
+                example_id = example.swag_id,
+                choices_features = choices_features,
+                label = label
+            )
+        )
+
+    return features
+
+def _truncate_seq_pair(tokens_a, tokens_b, max_length):
+    """Truncates a sequence pair in place to the maximum length."""
+
+    # This is a simple heuristic which will always truncate the longer sequence
+    # one token at a time. This makes more sense than truncating an equal percent
+    # of tokens from each, since if one sequence is very short then each token
+    # that's truncated likely contains more information than a longer sequence.
+    while True:
+        total_length = len(tokens_a) + len(tokens_b)
+        if total_length <= max_length:
+            break
+        if len(tokens_a) > len(tokens_b):
+            tokens_a.pop()
+        else:
+            tokens_b.pop()
+
+def accuracy(out, labels):
+    outputs = np.argmax(out, axis=1)
+    return np.sum(outputs == labels)
+
+def select_field(features, field):
+    return [
+        [
+            choice[field]
+            for choice in feature.choices_features
+        ]
+        for feature in features
+    ]
+
+
+def set_seed(args):
+    random.seed(args.seed)
+    np.random.seed(args.seed)
+    torch.manual_seed(args.seed)
+    if args.n_gpu > 0:
+        torch.cuda.manual_seed_all(args.seed)
+
+def load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False):
+    if args.local_rank not in [-1, 0]:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training process the dataset, and the others will use the cache
+
+    # Load data features from cache or dataset file
+    input_file = args.predict_file if evaluate else args.train_file
+    cached_features_file = os.path.join(os.path.dirname(input_file), 'cached_{}_{}_{}'.format(
+        'dev' if evaluate else 'train',
+        list(filter(None, args.model_name_or_path.split('/'))).pop(),
+        str(args.max_seq_length)))
+    if os.path.exists(cached_features_file) and not args.overwrite_cache and not output_examples:
+        logger.info("Loading features from cached file %s", cached_features_file)
+        features = torch.load(cached_features_file)
+    else:
+        logger.info("Creating features from dataset file at %s", input_file)
+        examples = read_swag_examples(input_file)
+        features = convert_examples_to_features(
+            examples, tokenizer, args.max_seq_length, not evaluate)
+
+        if args.local_rank in [-1, 0]:
+            logger.info("Saving features into cached file %s", cached_features_file)
+            torch.save(features, cached_features_file)
+
+    if args.local_rank == 0:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training process the dataset, and the others will use the cache
+
+    # Convert to Tensors and build dataset
+    all_input_ids = torch.tensor(select_field(features, 'input_ids'), dtype=torch.long)
+    all_input_mask = torch.tensor(select_field(features, 'input_mask'), dtype=torch.long)
+    all_segment_ids = torch.tensor(select_field(features, 'segment_ids'), dtype=torch.long)
+    all_label = torch.tensor([f.label for f in features], dtype=torch.long)
+
+    if evaluate:
+        dataset = TensorDataset(all_input_ids, all_input_mask, all_segment_ids,
+                                all_label)
+    else:
+        dataset = TensorDataset(all_input_ids, all_input_mask, all_segment_ids,
+                                all_label)
+
+    if output_examples:
+        return dataset, examples, features
+    return dataset
+def train(args, train_dataset, model, tokenizer):
+    """ Train the model """
+    if args.local_rank in [-1, 0]:
+        tb_writer = SummaryWriter()
+
+    args.train_batch_size = args.per_gpu_train_batch_size * max(1, args.n_gpu)
+    train_sampler = RandomSampler(train_dataset) if args.local_rank == -1 else DistributedSampler(train_dataset)
+    train_dataloader = DataLoader(train_dataset, sampler=train_sampler, batch_size=args.train_batch_size)
+
+    if args.max_steps > 0:
+        t_total = args.max_steps
+        args.num_train_epochs = args.max_steps // (len(train_dataloader) // args.gradient_accumulation_steps) + 1
+    else:
+        t_total = len(train_dataloader) // args.gradient_accumulation_steps * args.num_train_epochs
+
+    # Prepare optimizer and schedule (linear warmup and decay)
+    no_decay = ['bias', 'LayerNorm.weight']
+    optimizer_grouped_parameters = [
+        {'params': [p for n, p in model.named_parameters() if not any(nd in n for nd in no_decay)], 'weight_decay': args.weight_decay},
+        {'params': [p for n, p in model.named_parameters() if any(nd in n for nd in no_decay)], 'weight_decay': 0.0}
+        ]
+    optimizer = AdamW(optimizer_grouped_parameters, lr=args.learning_rate, eps=args.adam_epsilon)
+    scheduler = WarmupLinearSchedule(optimizer, warmup_steps=args.warmup_steps, t_total=t_total)
+    if args.fp16:
+        try:
+            from apex import amp
+        except ImportError:
+            raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use fp16 training.")
+        model, optimizer = amp.initialize(model, optimizer, opt_level=args.fp16_opt_level)
+
+    # multi-gpu training (should be after apex fp16 initialization)
+    if args.n_gpu > 1:
+        model = torch.nn.DataParallel(model)
+
+    # Distributed training (should be after apex fp16 initialization)
+    if args.local_rank != -1:
+        model = torch.nn.parallel.DistributedDataParallel(model, device_ids=[args.local_rank],
+                                                          output_device=args.local_rank,
+                                                          find_unused_parameters=True)
+
+    # Train!
+    logger.info("***** Running training *****")
+    logger.info("  Num examples = %d", len(train_dataset))
+    logger.info("  Num Epochs = %d", args.num_train_epochs)
+    logger.info("  Instantaneous batch size per GPU = %d", args.per_gpu_train_batch_size)
+    logger.info("  Total train batch size (w. parallel, distributed & accumulation) = %d",
+                   args.train_batch_size * args.gradient_accumulation_steps * (torch.distributed.get_world_size() if args.local_rank != -1 else 1))
+    logger.info("  Gradient Accumulation steps = %d", args.gradient_accumulation_steps)
+    logger.info("  Total optimization steps = %d", t_total)
+
+    global_step = 0
+    tr_loss, logging_loss = 0.0, 0.0
+    model.zero_grad()
+    train_iterator = trange(int(args.num_train_epochs), desc="Epoch", disable=args.local_rank not in [-1, 0])
+    set_seed(args)  # Added here for reproductibility (even between python 2 and 3)
+    for _ in train_iterator:
+        epoch_iterator = tqdm(train_dataloader, desc="Iteration", disable=args.local_rank not in [-1, 0])
+        for step, batch in enumerate(epoch_iterator):
+            model.train()
+            batch = tuple(t.to(args.device) for t in batch)
+            inputs = {'input_ids':       batch[0],
+                      'attention_mask':  batch[1],
+                      #'token_type_ids':  None if args.model_type == 'xlm' else batch[2],
+                      'token_type_ids': batch[2],
+                      'labels':         batch[3]}
+            # if args.model_type in ['xlnet', 'xlm']:
+            #     inputs.update({'cls_index': batch[5],
+            #                    'p_mask':       batch[6]})
+            outputs = model(**inputs)
+            loss = outputs[0]  # model outputs are always tuple in pytorch-transformers (see doc)
+
+            if args.n_gpu > 1:
+                loss = loss.mean() # mean() to average on multi-gpu parallel (not distributed) training
+            if args.gradient_accumulation_steps > 1:
+                loss = loss / args.gradient_accumulation_steps
+
+            if args.fp16:
+                with amp.scale_loss(loss, optimizer) as scaled_loss:
+                    scaled_loss.backward()
+                torch.nn.utils.clip_grad_norm_(amp.master_params(optimizer), args.max_grad_norm)
+            else:
+                loss.backward()
+                torch.nn.utils.clip_grad_norm_(model.parameters(), args.max_grad_norm)
+
+            tr_loss += loss.item()
+            if (step + 1) % args.gradient_accumulation_steps == 0:
+                optimizer.step()
+                scheduler.step()  # Update learning rate schedule
+                model.zero_grad()
+                global_step += 1
+
+                if args.local_rank in [-1, 0] and args.logging_steps > 0 and global_step % args.logging_steps == 0:
+                    # Log metrics
+                    if args.local_rank == -1 and args.evaluate_during_training:  # Only evaluate when single GPU otherwise metrics may not average well
+                        results = evaluate(args, model, tokenizer)
+                        for key, value in results.items():
+                            tb_writer.add_scalar('eval_{}'.format(key), value, global_step)
+                    tb_writer.add_scalar('lr', scheduler.get_lr()[0], global_step)
+                    tb_writer.add_scalar('loss', (tr_loss - logging_loss)/args.logging_steps, global_step)
+                    logging_loss = tr_loss
+
+                if args.local_rank in [-1, 0] and args.save_steps > 0 and global_step % args.save_steps == 0:
+                    # Save model checkpoint
+                    output_dir = os.path.join(args.output_dir, 'checkpoint-{}'.format(global_step))
+                    if not os.path.exists(output_dir):
+                        os.makedirs(output_dir)
+                    model_to_save = model.module if hasattr(model, 'module') else model  # Take care of distributed/parallel training
+                    model_to_save.save_pretrained(output_dir)
+                    tokenizer.save_vocabulary(output_dir)
+                    torch.save(args, os.path.join(output_dir, 'training_args.bin'))
+                    logger.info("Saving model checkpoint to %s", output_dir)
+
+            if args.max_steps > 0 and global_step > args.max_steps:
+                epoch_iterator.close()
+                break
+        if args.max_steps > 0 and global_step > args.max_steps:
+            train_iterator.close()
+            break
+
+    if args.local_rank in [-1, 0]:
+        tb_writer.close()
+
+    return global_step, tr_loss / global_step
+
+def evaluate(args, model, tokenizer, prefix=""):
+    dataset, examples, features = load_and_cache_examples(args, tokenizer, evaluate=True, output_examples=True)
+
+    if not os.path.exists(args.output_dir) and args.local_rank in [-1, 0]:
+        os.makedirs(args.output_dir)
+
+    args.eval_batch_size = args.per_gpu_eval_batch_size * max(1, args.n_gpu)
+    # Note that DistributedSampler samples randomly
+    eval_sampler = SequentialSampler(dataset) if args.local_rank == -1 else DistributedSampler(dataset)
+    eval_dataloader = DataLoader(dataset, sampler=eval_sampler, batch_size=args.eval_batch_size)
+
+    # Eval!
+    logger.info("***** Running evaluation {} *****".format(prefix))
+    logger.info("  Num examples = %d", len(dataset))
+    logger.info("  Batch size = %d", args.eval_batch_size)
+
+
+    eval_loss, eval_accuracy = 0, 0
+    nb_eval_steps, nb_eval_examples = 0, 0
+
+    for batch in tqdm(eval_dataloader, desc="Evaluating"):
+        model.eval()
+        batch = tuple(t.to(args.device) for t in batch)
+        with torch.no_grad():
+            inputs = {'input_ids':      batch[0],
+                      'attention_mask': batch[1],
+                      # 'token_type_ids': None if args.model_type == 'xlm' else batch[2]  # XLM don't use segment_ids
+                      'token_type_ids': batch[2],
+                      'labels':         batch[3]}
+
+            # if args.model_type in ['xlnet', 'xlm']:
+            #     inputs.update({'cls_index': batch[4],
+            #                    'p_mask':    batch[5]})
+            outputs = model(**inputs)
+            tmp_eval_loss, logits = outputs[:2]
+            eval_loss += tmp_eval_loss.mean().item()
+
+        logits = logits.detach().cpu().numpy()
+        label_ids = inputs['labels'].to('cpu').numpy()
+        tmp_eval_accuracy = accuracy(logits, label_ids)
+        eval_accuracy += tmp_eval_accuracy
+
+        nb_eval_steps += 1
+        nb_eval_examples += inputs['input_ids'].size(0)
+
+    eval_loss = eval_loss / nb_eval_steps
+    eval_accuracy = eval_accuracy / nb_eval_examples
+    result = {'eval_loss': eval_loss,
+              'eval_accuracy': eval_accuracy}
+
+    output_eval_file = os.path.join(args.output_dir, "eval_results.txt")
+    with open(output_eval_file, "w") as writer:
+        logger.info("***** Eval results *****")
+        for key in sorted(result.keys()):
+            logger.info("%s = %s", key, str(result[key]))
+            writer.write("%s = %s\n" % (key, str(result[key])))
+
+    return result
+
+def main():
+    parser = argparse.ArgumentParser()
+
+    ## Required parameters
+    parser.add_argument("--train_file", default=None, type=str, required=True,
+                        help="SWAG csv for training. E.g., train.csv")
+    parser.add_argument("--predict_file", default=None, type=str, required=True,
+                        help="SWAG csv for predictions. E.g., val.csv or test.csv")
+    parser.add_argument("--model_type", default=None, type=str, required=True,
+                        help="Model type selected in the list: " + ", ".join(MODEL_CLASSES.keys()))
+    parser.add_argument("--model_name_or_path", default=None, type=str, required=True,
+                        help="Path to pre-trained model or shortcut name selected in the list: " + ", ".join(ALL_MODELS))
+    parser.add_argument("--output_dir", default=None, type=str, required=True,
+                        help="The output directory where the model checkpoints and predictions will be written.")
+
+    ## Other parameters
+    parser.add_argument("--config_name", default="", type=str,
+                        help="Pretrained config name or path if not the same as model_name")
+    parser.add_argument("--tokenizer_name", default="", type=str,
+                        help="Pretrained tokenizer name or path if not the same as model_name")
+    parser.add_argument("--max_seq_length", default=384, type=int,
+                        help="The maximum total input sequence length after tokenization. Sequences "
+                             "longer than this will be truncated, and sequences shorter than this will be padded.")
+    parser.add_argument("--do_train", action='store_true',
+                        help="Whether to run training.")
+    parser.add_argument("--do_eval", action='store_true',
+                        help="Whether to run eval on the dev set.")
+    parser.add_argument("--evaluate_during_training", action='store_true',
+                        help="Rul evaluation during training at each logging step.")
+    parser.add_argument("--do_lower_case", action='store_true',
+                        help="Set this flag if you are using an uncased model.")
+
+    parser.add_argument("--per_gpu_train_batch_size", default=8, type=int,
+                        help="Batch size per GPU/CPU for training.")
+    parser.add_argument("--per_gpu_eval_batch_size", default=8, type=int,
+                        help="Batch size per GPU/CPU for evaluation.")
+    parser.add_argument("--learning_rate", default=5e-5, type=float,
+                        help="The initial learning rate for Adam.")
+    parser.add_argument('--gradient_accumulation_steps', type=int, default=1,
+                        help="Number of updates steps to accumulate before performing a backward/update pass.")
+    parser.add_argument("--weight_decay", default=0.0, type=float,
+                        help="Weight deay if we apply some.")
+    parser.add_argument("--adam_epsilon", default=1e-8, type=float,
+                        help="Epsilon for Adam optimizer.")
+    parser.add_argument("--max_grad_norm", default=1.0, type=float,
+                        help="Max gradient norm.")
+    parser.add_argument("--num_train_epochs", default=3.0, type=float,
+                        help="Total number of training epochs to perform.")
+    parser.add_argument("--max_steps", default=-1, type=int,
+                        help="If > 0: set total number of training steps to perform. Override num_train_epochs.")
+    parser.add_argument("--warmup_steps", default=0, type=int,
+                        help="Linear warmup over warmup_steps.")
+
+    parser.add_argument('--logging_steps', type=int, default=50,
+                        help="Log every X updates steps.")
+    parser.add_argument('--save_steps', type=int, default=50,
+                        help="Save checkpoint every X updates steps.")
+    parser.add_argument("--eval_all_checkpoints", action='store_true',
+                        help="Evaluate all checkpoints starting with the same prefix as model_name ending and ending with step number")
+    parser.add_argument("--no_cuda", action='store_true',
+                        help="Whether not to use CUDA when available")
+    parser.add_argument('--overwrite_output_dir', action='store_true',
+                        help="Overwrite the content of the output directory")
+    parser.add_argument('--overwrite_cache', action='store_true',
+                        help="Overwrite the cached training and evaluation sets")
+    parser.add_argument('--seed', type=int, default=42,
+                        help="random seed for initialization")
+
+    parser.add_argument("--local_rank", type=int, default=-1,
+                        help="local_rank for distributed training on gpus")
+    parser.add_argument('--fp16', action='store_true',
+                        help="Whether to use 16-bit (mixed) precision (through NVIDIA apex) instead of 32-bit")
+    parser.add_argument('--fp16_opt_level', type=str, default='O1',
+                        help="For fp16: Apex AMP optimization level selected in ['O0', 'O1', 'O2', and 'O3']."
+                             "See details at https://nvidia.github.io/apex/amp.html")
+    parser.add_argument('--server_ip', type=str, default='', help="Can be used for distant debugging.")
+    parser.add_argument('--server_port', type=str, default='', help="Can be used for distant debugging.")
+    args = parser.parse_args()
+
+    if os.path.exists(args.output_dir) and os.listdir(args.output_dir) and args.do_train and not args.overwrite_output_dir:
+        raise ValueError("Output directory ({}) already exists and is not empty. Use --overwrite_output_dir to overcome.".format(args.output_dir))
+
+    # Setup distant debugging if needed
+    if args.server_ip and args.server_port:
+        # Distant debugging - see https://code.visualstudio.com/docs/python/debugging#_attach-to-a-local-script
+        import ptvsd
+        print("Waiting for debugger attach")
+        ptvsd.enable_attach(address=(args.server_ip, args.server_port), redirect_output=True)
+        ptvsd.wait_for_attach()
+
+    # Setup CUDA, GPU & distributed training
+    if args.local_rank == -1 or args.no_cuda:
+        device = torch.device("cuda" if torch.cuda.is_available() and not args.no_cuda else "cpu")
+        args.n_gpu = torch.cuda.device_count()
+    else:  # Initializes the distributed backend which will take care of sychronizing nodes/GPUs
+        torch.cuda.set_device(args.local_rank)
+        device = torch.device("cuda", args.local_rank)
+        torch.distributed.init_process_group(backend='nccl')
+        args.n_gpu = 1
+    args.device = device
+
+    # Setup logging
+    logging.basicConfig(format = '%(asctime)s - %(levelname)s - %(name)s -   %(message)s',
+                        datefmt = '%m/%d/%Y %H:%M:%S',
+                        level = logging.INFO if args.local_rank in [-1, 0] else logging.WARN)
+    logger.warning("Process rank: %s, device: %s, n_gpu: %s, distributed training: %s, 16-bits training: %s",
+                    args.local_rank, device, args.n_gpu, bool(args.local_rank != -1), args.fp16)
+
+    # Set seed
+    set_seed(args)
+
+    # Load pretrained model and tokenizer
+    if args.local_rank not in [-1, 0]:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training will download model & vocab
+
+    args.model_type = args.model_type.lower()
+    config_class, model_class, tokenizer_class = MODEL_CLASSES[args.model_type]
+    config = config_class.from_pretrained(args.config_name if args.config_name else args.model_name_or_path)
+    tokenizer = tokenizer_class.from_pretrained(args.tokenizer_name if args.tokenizer_name else args.model_name_or_path, do_lower_case=args.do_lower_case)
+    model = model_class.from_pretrained(args.model_name_or_path, from_tf=bool('.ckpt' in args.model_name_or_path), config=config)
+
+    if args.local_rank == 0:
+        torch.distributed.barrier()  # Make sure only the first process in distributed training will download model & vocab
+
+    model.to(args.device)
+
+    logger.info("Training/evaluation parameters %s", args)
+
+    # Training
+    if args.do_train:
+        train_dataset = load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False)
+        global_step, tr_loss = train(args, train_dataset, model, tokenizer)
+        logger.info(" global_step = %s, average loss = %s", global_step, tr_loss)
+
+
+    # Save the trained model and the tokenizer
+    if args.local_rank == -1 or torch.distributed.get_rank() == 0:
+        # Create output directory if needed
+        if not os.path.exists(args.output_dir) and args.local_rank in [-1, 0]:
+            os.makedirs(args.output_dir)
+
+        logger.info("Saving model checkpoint to %s", args.output_dir)
+        # Save a trained model, configuration and tokenizer using `save_pretrained()`.
+        # They can then be reloaded using `from_pretrained()`
+        model_to_save = model.module if hasattr(model, 'module') else model  # Take care of distributed/parallel training
+        model_to_save.save_pretrained(args.output_dir)
+        tokenizer.save_pretrained(args.output_dir)
+
+        # Good practice: save your training arguments together with the trained model
+        torch.save(args, os.path.join(args.output_dir, 'training_args.bin'))
+
+        # Load a trained model and vocabulary that you have fine-tuned
+        model = model_class.from_pretrained(args.output_dir)
+        tokenizer = tokenizer_class.from_pretrained(args.output_dir)
+        model.to(args.device)
+
+
+    # Evaluation - we can ask to evaluate all the checkpoints (sub-directories) in a directory
+    results = {}
+    if args.do_eval and args.local_rank in [-1, 0]:
+        if args.do_train:
+            checkpoints = [args.output_dir]
+        else:
+            # if do_train is False and do_eval is true, load model directly from pretrained.
+            checkpoints = [args.model_name_or_path]
+
+        if args.eval_all_checkpoints:
+            checkpoints = list(os.path.dirname(c) for c in sorted(glob.glob(args.output_dir + '/**/' + WEIGHTS_NAME, recursive=True)))
+            logging.getLogger("pytorch_transformers.modeling_utils").setLevel(logging.WARN)  # Reduce model loading logs
+
+        logger.info("Evaluate the following checkpoints: %s", checkpoints)
+
+        for checkpoint in checkpoints:
+            # Reload the model
+            global_step = checkpoint.split('-')[-1] if len(checkpoints) > 1 else ""
+            model = model_class.from_pretrained(checkpoint)
+            tokenizer = tokenizer_class.from_pretrained(checkpoint)
+            model.to(args.device)
+
+            # Evaluate
+            result = evaluate(args, model, tokenizer, prefix=global_step)
+
+            result = dict((k + ('_{}'.format(global_step) if global_step else ''), v) for k, v in result.items())
+            results.update(result)
+
+    logger.info("Results: {}".format(results))
+
+    return results
+
+
+if __name__ == "__main__":
+    main()

examples/contrib/run_transfo_xl.py

@@ -0,0 +1,153 @@
+# coding=utf-8
+# Copyright 2018 Google AI, Google Brain and Carnegie Mellon University Authors and the HuggingFace Inc. team.
+# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+""" PyTorch Transformer XL model evaluation script.
+    Adapted from https://github.com/kimiyoung/transformer-xl.
+    In particular https://github.com/kimiyoung/transformer-xl/blob/master/pytorch/eval.py
+
+    This script with default values evaluates a pretrained Transformer-XL on WikiText 103
+"""
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+import argparse
+import logging
+import time
+import math
+
+import torch
+
+from pytorch_transformers import TransfoXLLMHeadModel, TransfoXLCorpus, TransfoXLTokenizer
+
+logging.basicConfig(format = '%(asctime)s - %(levelname)s - %(name)s -   %(message)s',
+                    datefmt = '%m/%d/%Y %H:%M:%S',
+                    level = logging.INFO)
+logger = logging.getLogger(__name__)
+
+def main():
+    parser = argparse.ArgumentParser(description='PyTorch Transformer Language Model')
+    parser.add_argument('--model_name', type=str, default='transfo-xl-wt103',
+                        help='pretrained model name')
+    parser.add_argument('--split', type=str, default='test',
+                        choices=['all', 'valid', 'test'],
+                        help='which split to evaluate')
+    parser.add_argument('--batch_size', type=int, default=10,
+                        help='batch size')
+    parser.add_argument('--tgt_len', type=int, default=128,
+                        help='number of tokens to predict')
+    parser.add_argument('--ext_len', type=int, default=0,
+                        help='length of the extended context')
+    parser.add_argument('--mem_len', type=int, default=1600,
+                        help='length of the retained previous heads')
+    parser.add_argument('--clamp_len', type=int, default=1000,
+                        help='max positional embedding index')
+    parser.add_argument('--no_cuda', action='store_true',
+                        help='Do not use CUDA even though CUA is available')
+    parser.add_argument('--work_dir', type=str, required=True,
+                        help='path to the work_dir')
+    parser.add_argument('--no_log', action='store_true',
+                        help='do not log the eval result')
+    parser.add_argument('--same_length', action='store_true',
+                        help='set same length attention with masking')
+    parser.add_argument('--server_ip', type=str, default='', help="Can be used for distant debugging.")
+    parser.add_argument('--server_port', type=str, default='', help="Can be used for distant debugging.")
+    args = parser.parse_args()
+    assert args.ext_len >= 0, 'extended context length must be non-negative'
+
+    if args.server_ip and args.server_port:
+        # Distant debugging - see https://code.visualstudio.com/docs/python/debugging#_attach-to-a-local-script
+        import ptvsd
+        print("Waiting for debugger attach")
+        ptvsd.enable_attach(address=(args.server_ip, args.server_port), redirect_output=True)
+        ptvsd.wait_for_attach()
+
+    device = torch.device("cuda" if torch.cuda.is_available() and not args.no_cuda else "cpu")
+    logger.info("device: {}".format(device))
+
+    # Load a pre-processed dataset
+    # You can also build the corpus yourself using TransfoXLCorpus methods
+    # The pre-processing involve computing word frequencies to prepare the Adaptive input and SoftMax
+    # and tokenizing the dataset
+    # The pre-processed corpus is a convertion (using the conversion script )
+    tokenizer = TransfoXLTokenizer.from_pretrained(args.model_name)
+    corpus = TransfoXLCorpus.from_pretrained(args.model_name)
+    ntokens = len(corpus.vocab)
+
+    va_iter = corpus.get_iterator('valid', args.batch_size, args.tgt_len,
+        device=device, ext_len=args.ext_len)
+    te_iter = corpus.get_iterator('test', args.batch_size, args.tgt_len,
+        device=device, ext_len=args.ext_len)
+
+    # Load a pre-trained model
+    model = TransfoXLLMHeadModel.from_pretrained(args.model_name)
+    model = model.to(device)
+
+    logger.info('Evaluating with bsz {} tgt_len {} ext_len {} mem_len {} clamp_len {}'.format(
+        args.batch_size, args.tgt_len, args.ext_len, args.mem_len, args.clamp_len))
+
+    model.reset_length(args.tgt_len, args.ext_len, args.mem_len)
+    if args.clamp_len > 0:
+        model.clamp_len = args.clamp_len
+    if args.same_length:
+        model.same_length = True
+
+    ###############################################################################
+    # Evaluation code
+    ###############################################################################
+    def evaluate(eval_iter):
+        # Turn on evaluation mode which disables dropout.
+        model.eval()
+        total_len, total_loss = 0, 0.
+        start_time = time.time()
+        with torch.no_grad():
+            mems = None
+            for idx, (data, target, seq_len) in enumerate(eval_iter):
+                ret = model(data, lm_labels=target, mems=mems)
+                loss, _, mems = ret
+                loss = loss.mean()
+                total_loss += seq_len * loss.item()
+                total_len += seq_len
+            total_time = time.time() - start_time
+        logger.info('Time : {:.2f}s, {:.2f}ms/segment'.format(
+                total_time, 1000 * total_time / (idx+1)))
+        return total_loss / total_len
+
+    # Run on test data.
+    if args.split == 'all':
+        test_loss = evaluate(te_iter)
+        valid_loss = evaluate(va_iter)
+    elif args.split == 'valid':
+        valid_loss = evaluate(va_iter)
+        test_loss = None
+    elif args.split == 'test':
+        test_loss = evaluate(te_iter)
+        valid_loss = None
+
+    def format_log(loss, split):
+        log_str = '| {0} loss {1:5.2f} | {0} ppl {2:9.3f} '.format(
+            split, loss, math.exp(loss))
+        return log_str
+
+    log_str = ''
+    if valid_loss is not None:
+        log_str += format_log(valid_loss, 'valid')
+    if test_loss is not None:
+        log_str += format_log(test_loss, 'test')
+
+    logger.info('=' * 100)
+    logger.info(log_str)
+    logger.info('=' * 100)
+
+if __name__ == '__main__':
+    main()

examples/contrib/utils_multiple_choice.py

@@ -0,0 +1,452 @@
+# coding=utf-8
+# Copyright 2018 The Google AI Language Team Authors and The HuggingFace Inc. team.
+# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+""" BERT classification fine-tuning: utilities to work with GLUE tasks """
+
+from __future__ import absolute_import, division, print_function
+
+
+import logging
+import os
+import sys
+from io import open
+import json
+import csv
+import glob
+import tqdm
+
+
+logger = logging.getLogger(__name__)
+
+
+class InputExample(object):
+    """A single training/test example for multiple choice"""
+
+    def __init__(self, example_id, question,  contexts, endings, label=None):
+        """Constructs a InputExample.
+
+        Args:
+            guid: Unique id for the example.
+            text_a: string. The untokenized text of the first sequence. For single
+            sequence tasks, only this sequence must be specified.
+            text_b: (Optional) string. The untokenized text of the second sequence.
+            Only must be specified for sequence pair tasks.
+            label: (Optional) string. The label of the example. This should be
+            specified for train and dev examples, but not for test examples.
+        """
+        self.example_id = example_id
+        self.question = question
+        self.contexts = contexts
+        self.endings = endings
+        self.label = label
+
+
+class InputFeatures(object):
+    def __init__(self,
+                 example_id,
+                 choices_features,
+                 label
+
+    ):
+        self.example_id = example_id
+        self.choices_features = [
+            {
+                'input_ids': input_ids,
+                'input_mask': input_mask,
+                'segment_ids': segment_ids
+            }
+            for _, input_ids, input_mask, segment_ids in choices_features
+        ]
+        self.label = label
+
+
+class DataProcessor(object):
+    """Base class for data converters for sequence classification data sets."""
+
+    def get_train_examples(self, data_dir):
+        """Gets a collection of `InputExample`s for the train set."""
+        raise NotImplementedError()
+
+    def get_dev_examples(self, data_dir):
+        """Gets a collection of `InputExample`s for the dev set."""
+        raise NotImplementedError()
+
+    def get_test_examples(self, data_dir):
+        """Gets a collection of `InputExample`s for the dev set."""
+        raise NotImplementedError()
+
+    def get_labels(self):
+        """Gets the list of labels for this data set."""
+        raise NotImplementedError()
+
+
+class RaceProcessor(DataProcessor):
+    """Processor for the MRPC data set (GLUE version)."""
+
+    def get_train_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} train".format(data_dir))
+        high = os.path.join(data_dir, 'train/high')
+        middle = os.path.join(data_dir, 'train/middle')
+        high = self._read_txt(high)
+        middle = self._read_txt(middle)
+        return self._create_examples(high + middle, 'train')
+
+    def get_dev_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        high = os.path.join(data_dir, 'dev/high')
+        middle = os.path.join(data_dir, 'dev/middle')
+        high = self._read_txt(high)
+        middle = self._read_txt(middle)
+        return self._create_examples(high + middle, 'dev')
+
+    def get_test_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} test".format(data_dir))
+        high = os.path.join(data_dir, 'test/high')
+        middle = os.path.join(data_dir, 'test/middle')
+        high = self._read_txt(high)
+        middle = self._read_txt(middle)
+        return self._create_examples(high + middle, 'test')
+
+    def get_labels(self):
+        """See base class."""
+        return ["0", "1", "2", "3"]
+
+    def _read_txt(self, input_dir):
+        lines = []
+        files = glob.glob(input_dir + "/*txt")
+        for file in tqdm.tqdm(files, desc="read files"):
+            with open(file, 'r', encoding='utf-8') as fin:
+                data_raw = json.load(fin)
+                data_raw["race_id"] = file
+                lines.append(data_raw)
+        return lines
+
+
+    def _create_examples(self, lines, set_type):
+        """Creates examples for the training and dev sets."""
+        examples = []
+        for (_, data_raw) in enumerate(lines):
+            race_id = "%s-%s" % (set_type, data_raw["race_id"])
+            article = data_raw["article"]
+            for i in range(len(data_raw["answers"])):
+                truth = str(ord(data_raw['answers'][i]) - ord('A'))
+                question = data_raw['questions'][i]
+                options = data_raw['options'][i]
+
+                examples.append(
+                    InputExample(
+                        example_id=race_id,
+                        question=question,
+                        contexts=[article, article, article, article],
+                        endings=[options[0], options[1], options[2], options[3]],
+                        label=truth))
+        return examples
+
+class SwagProcessor(DataProcessor):
+    """Processor for the MRPC data set (GLUE version)."""
+
+    def get_train_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} train".format(data_dir))
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "train.csv")), "train")
+
+    def get_dev_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "val.csv")), "dev")
+
+    def get_test_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} test".format(data_dir))
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "test.csv")), "test")
+
+    def get_labels(self):
+        """See base class."""
+        return ["0", "1", "2", "3"]
+
+    def _read_csv(self, input_file):
+        with open(input_file, 'r', encoding='utf-8') as f:
+            reader = csv.reader(f)
+            lines = []
+            for line in reader:
+                if sys.version_info[0] == 2:
+                    line = list(unicode(cell, 'utf-8') for cell in line)
+                lines.append(line)
+            return lines
+
+
+    def _create_examples(self, lines, type):
+        """Creates examples for the training and dev sets."""
+        if type == "train" and lines[0][-1] != 'label':
+            raise ValueError(
+                "For training, the input file must contain a label column."
+            )
+
+        examples = [
+            InputExample(
+                example_id=line[2],
+                question=line[5],  # in the swag dataset, the
+                # common beginning of each
+                # choice is stored in "sent2".
+                contexts = [line[4], line[4], line[4], line[4]],
+                endings = [line[7], line[8], line[9], line[10]],
+                label=line[11]
+            ) for line in lines[1:]  # we skip the line with the column names
+        ]
+
+        return examples
+
+
+class ArcProcessor(DataProcessor):
+    """Processor for the MRPC data set (GLUE version)."""
+
+    def get_train_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} train".format(data_dir))
+        return self._create_examples(self._read_json(os.path.join(data_dir, "train.jsonl")), "train")
+
+    def get_dev_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        return self._create_examples(self._read_json(os.path.join(data_dir, "dev.jsonl")), "dev")
+
+    def get_test_examples(self, data_dir):
+        logger.info("LOOKING AT {} test".format(data_dir))
+        return self._create_examples(self._read_json(os.path.join(data_dir, "test.jsonl")), "test")
+
+    def get_labels(self):
+        """See base class."""
+        return ["0", "1", "2", "3"]
+
+    def _read_json(self, input_file):
+        with open(input_file, 'r', encoding='utf-8') as fin:
+            lines = fin.readlines()
+            return lines
+
+
+    def _create_examples(self, lines, type):
+        """Creates examples for the training and dev sets."""
+
+        def normalize(truth):
+            if truth in "ABCD":
+                return ord(truth) - ord("A")
+            elif truth in "1234":
+                return int(truth) - 1
+            else:
+                logger.info("truth ERROR! %s", str(truth))
+                return None
+
+        examples = []
+        three_choice = 0
+        four_choice = 0
+        five_choice = 0
+        other_choices = 0
+        for line in tqdm.tqdm(lines, desc="read arc data"):
+            data_raw = json.loads(line.strip("\n"))
+            if len(data_raw["question"]["choices"]) == 3:
+                three_choice += 1
+                continue
+            elif len(data_raw["question"]["choices"]) == 5:
+                five_choice += 1
+                continue
+            elif len(data_raw["question"]["choices"]) != 4:
+                other_choices += 1
+                continue
+            four_choice += 1
+            truth = str(normalize(data_raw["answerKey"]))
+            assert truth != "None"
+            question_choices = data_raw["question"]
+            question = question_choices["stem"]
+            id = data_raw["id"]
+            options = question_choices["choices"]
+
+            if len(options) == 4:
+                examples.append(
+                    InputExample(
+                        example_id = id,
+                        question=question,
+                        contexts=[options[0]["para"].replace("_", ""), options[1]["para"].replace("_", ""),
+                                  options[2]["para"].replace("_", ""), options[3]["para"].replace("_", "")],
+                        endings=[options[0]["text"], options[1]["text"], options[2]["text"], options[3]["text"]],
+                        label=truth))
+
+        if type == "train":
+            assert len(examples) > 1
+            assert examples[0].label is not None
+        logger.info("len examples: %s}", str(len(examples)))
+        logger.info("Three choices: %s", str(three_choice))
+        logger.info("Five choices: %s", str(five_choice))
+        logger.info("Other choices: %s", str(other_choices))
+        logger.info("four choices: %s", str(four_choice))
+
+        return examples
+
+
+def convert_examples_to_features(examples, label_list, max_seq_length,
+                                 tokenizer,
+                                 cls_token_at_end=False,
+                                 cls_token='[CLS]',
+                                 cls_token_segment_id=1,
+                                 sep_token='[SEP]',
+                                 sequence_a_segment_id=0,
+                                 sequence_b_segment_id=1,
+                                 sep_token_extra=False,
+                                 pad_token_segment_id=0,
+                                 pad_on_left=False,
+                                 pad_token=0,
+                                 mask_padding_with_zero=True):
+    """ Loads a data file into a list of `InputBatch`s
+        `cls_token_at_end` define the location of the CLS token:
+            - False (Default, BERT/XLM pattern): [CLS] + A + [SEP] + B + [SEP]
+            - True (XLNet/GPT pattern): A + [SEP] + B + [SEP] + [CLS]
+        `cls_token_segment_id` define the segment id associated to the CLS token (0 for BERT, 2 for XLNet)
+    """
+
+    label_map = {label : i for i, label in enumerate(label_list)}
+
+    features = []
+    for (ex_index, example) in tqdm.tqdm(enumerate(examples), desc="convert examples to features"):
+        if ex_index % 10000 == 0:
+            logger.info("Writing example %d of %d" % (ex_index, len(examples)))
+        choices_features = []
+        for ending_idx, (context, ending) in enumerate(zip(example.contexts, example.endings)):
+            tokens_a = tokenizer.tokenize(context)
+            tokens_b = None
+            if example.question.find("_") != -1:
+                tokens_b = tokenizer.tokenize(example.question.replace("_", ending))
+            else:
+                tokens_b = tokenizer.tokenize(example.question)
+                tokens_b += [sep_token]
+                if sep_token_extra:
+                    tokens_b += [sep_token]
+                tokens_b += tokenizer.tokenize(ending)
+
+            special_tokens_count = 4 if sep_token_extra else 3
+            _truncate_seq_pair(tokens_a, tokens_b, max_seq_length - special_tokens_count)
+
+            # The convention in BERT is:
+            # (a) For sequence pairs:
+            #  tokens:   [CLS] is this jack ##son ##ville ? [SEP] no it is not . [SEP]
+            #  type_ids:   0   0  0    0    0     0       0   0   1  1  1  1   1   1
+            # (b) For single sequences:
+            #  tokens:   [CLS] the dog is hairy . [SEP]
+            #  type_ids:   0   0   0   0  0     0   0
+            #
+            # Where "type_ids" are used to indicate whether this is the first
+            # sequence or the second sequence. The embedding vectors for `type=0` and
+            # `type=1` were learned during pre-training and are added to the wordpiece
+            # embedding vector (and position vector). This is not *strictly* necessary
+            # since the [SEP] token unambiguously separates the sequences, but it makes
+            # it easier for the model to learn the concept of sequences.
+            #
+            # For classification tasks, the first vector (corresponding to [CLS]) is
+            # used as as the "sentence vector". Note that this only makes sense because
+            # the entire model is fine-tuned.
+            tokens = tokens_a + [sep_token]
+            if sep_token_extra:
+                # roberta uses an extra separator b/w pairs of sentences
+                tokens += [sep_token]
+
+            segment_ids = [sequence_a_segment_id] * len(tokens)
+
+            if tokens_b:
+                tokens += tokens_b + [sep_token]
+                segment_ids += [sequence_b_segment_id] * (len(tokens_b) + 1)
+
+            if cls_token_at_end:
+                tokens = tokens + [cls_token]
+                segment_ids = segment_ids + [cls_token_segment_id]
+            else:
+                tokens = [cls_token] + tokens
+                segment_ids = [cls_token_segment_id] + segment_ids
+
+            input_ids = tokenizer.convert_tokens_to_ids(tokens)
+
+            # The mask has 1 for real tokens and 0 for padding tokens. Only real
+            # tokens are attended to.
+            input_mask = [1 if mask_padding_with_zero else 0] * len(input_ids)
+
+            # Zero-pad up to the sequence length.
+            padding_length = max_seq_length - len(input_ids)
+            if pad_on_left:
+                input_ids = ([pad_token] * padding_length) + input_ids
+                input_mask = ([0 if mask_padding_with_zero else 1] * padding_length) + input_mask
+                segment_ids = ([pad_token_segment_id] * padding_length) + segment_ids
+            else:
+                input_ids = input_ids + ([pad_token] * padding_length)
+                input_mask = input_mask + ([0 if mask_padding_with_zero else 1] * padding_length)
+                segment_ids = segment_ids + ([pad_token_segment_id] * padding_length)
+
+            assert len(input_ids) == max_seq_length
+            assert len(input_mask) == max_seq_length
+            assert len(segment_ids) == max_seq_length
+            choices_features.append((tokens, input_ids, input_mask, segment_ids))
+        label = label_map[example.label]
+
+        if ex_index < 2:
+            logger.info("*** Example ***")
+            logger.info("race_id: {}".format(example.example_id))
+            for choice_idx, (tokens, input_ids, input_mask, segment_ids) in enumerate(choices_features):
+                logger.info("choice: {}".format(choice_idx))
+                logger.info("tokens: {}".format(' '.join(tokens)))
+                logger.info("input_ids: {}".format(' '.join(map(str, input_ids))))
+                logger.info("input_mask: {}".format(' '.join(map(str, input_mask))))
+                logger.info("segment_ids: {}".format(' '.join(map(str, segment_ids))))
+                logger.info("label: {}".format(label))
+
+        features.append(
+            InputFeatures(
+                example_id = example.example_id,
+                choices_features = choices_features,
+                label = label
+            )
+        )
+
+    return features
+
+
+def _truncate_seq_pair(tokens_a, tokens_b, max_length):
+    """Truncates a sequence pair in place to the maximum length."""
+
+    # This is a simple heuristic which will always truncate the longer sequence
+    # one token at a time. This makes more sense than truncating an equal percent
+    # of tokens from each, since if one sequence is very short then each token
+    # that's truncated likely contains more information than a longer sequence.
+    while True:
+        total_length = len(tokens_a) + len(tokens_b)
+        if total_length <= max_length:
+            break
+        # if len(tokens_a) > len(tokens_b):
+        #     tokens_a.pop()
+        # else:
+        #     tokens_b.pop()
+        tokens_a.pop()
+
+
+processors = {
+    "race": RaceProcessor,
+    "swag": SwagProcessor,
+    "arc": ArcProcessor
+}
+
+
+GLUE_TASKS_NUM_LABELS = {
+    "race", 4,
+    "swag", 4,
+    "arc", 4
+}