Use Python 3.9 syntax in examples (#37279)

Signed-off-by: cyy <cyyever@outlook.com>

examples/pytorch/text-generation/run_generation.py

@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# 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.
 #
@@ -19,7 +18,6 @@
 import argparse
 import inspect
 import logging
-from typing import Tuple
 
 import torch
 from accelerate import PartialState
@@ -271,8 +269,8 @@ class _ModelFallbackWrapper(GenerationMixin):
         )
 
     def _reorder_cache(
-        self, past_key_values: Tuple[Tuple[torch.Tensor]], beam_idx: torch.Tensor
-    ) -> Tuple[Tuple[torch.Tensor]]:
+        self, past_key_values: tuple[tuple[torch.Tensor]], beam_idx: torch.Tensor
+    ) -> tuple[tuple[torch.Tensor]]:
         """
         This function is used to re-order the `past_key_values` cache if [`~PretrainedModel.beam_search`] or
         [`~PretrainedModel.beam_sample`] is called. This is required to match `past_key_values` with the correct

examples/pytorch/text-generation/run_generation_contrastive_search.py

@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# coding=utf-8
 # Copyright 2022 University of Cambridge, Tencent AI Lab, DeepMind and The University of Hong Kong Authors and The HuggingFace Inc. team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");