[s2s] add create student script (#7290)

Co-authored-by: Suraj Patil <surajp815@gmail.com>
Co-authored-by: Sam Shleifer <sshleifer@gmail.com>

examples/seq2seq/save_randomly_initialized_model.py

@@ -0,0 +1,26 @@
+#!/usr/bin/env python
+
+import fire
+
+from transformers import AutoConfig, AutoModelForSeq2SeqLM, AutoTokenizer
+
+
+def save_randomly_initialized_version(config_name: str, save_dir: str, **config_kwargs):
+    """Save a randomly initialized version of a model using a pretrained config.
+    Args:
+        config_name: which config to use
+        save_dir: where to save the resulting model and tokenizer
+        config_kwargs: Passed to AutoConfig
+
+    Usage::
+        save_randomly_initialized_version("facebook/bart-large-cnn", "distilbart_random_cnn_6_3", encoder_layers=6, decoder_layers=3, num_beams=3)
+    """
+    cfg = AutoConfig.from_pretrained(config_name, **config_kwargs)
+    model = AutoModelForSeq2SeqLM.from_config(cfg)
+    model.save_pretrained(save_dir)
+    AutoTokenizer.from_pretrained(config_name).save_pretrained(save_dir)
+    return model
+
+
+if __name__ == "__main__":
+    fire.Fire(save_randomly_initialized_version)