Code parrot minor fixes/niceties (#14666)

* Add some nicety flags for better controlling evaluation.

* Fix dependency issue with outdated requirement

* Add additional flag to example to ensure eval is done

* Wrap code into main function for accelerate launcher to find

* Fix valid batch size flag in readme

* Add note to install git-lfs when initializing/training the model

* Update examples/research_projects/codeparrot/scripts/arguments.py

Co-authored-by: Leandro von Werra <lvwerra@users.noreply.github.com>

* Update examples/research_projects/codeparrot/README.md

Co-authored-by: Leandro von Werra <lvwerra@users.noreply.github.com>

* Revert "Wrap code into main function for accelerate launcher to find"

This reverts commit ff11df1c810d4df198d04b827538eb4572147ba3.

* Fix formatting issue

* Move git-lfs instructions to installation section

* Add a quick check before code generation for code evaluation

* Fix styling issue

* Update examples/research_projects/codeparrot/scripts/human_eval.py

Co-authored-by: Leandro von Werra <lvwerra@users.noreply.github.com>

* Make iterable dataset use passed in tokenizer rather than globally defined one

Co-authored-by: Leandro von Werra <lvwerra@users.noreply.github.com>
Co-authored-by: ncoop57 <nac33@students.uwf.edu>

examples/research_projects/codeparrot/scripts/codeparrot_training.py

@@ -59,7 +59,7 @@ class ConstantLengthDataset(IterableDataset):
                     else:
                         more_examples = False
                         break
-            tokenized_inputs = tokenizer(buffer, truncation=False)["input_ids"]
+            tokenized_inputs = self.tokenizer(buffer, truncation=False)["input_ids"]
             all_token_ids = []
             for tokenized_input in tokenized_inputs:
                 all_token_ids.extend(tokenized_input + [self.concat_token_id])