* [dygraph]unify _non_static_mode() in_dygraph_mode() and in_dynamic_mode()

* [dygraph]unify _non_static_mode() in_dygraph_mode() and in_dynamic_mode()

* [dygraph]unify _non_static_mode() in_dygraph_mode() and in_dynamic_mode()

* [dygraph]unify _non_static_mode() in_dygraph_mode() and in_dynamic_mode()

* [dygraph]unify _non_static_mode() in_dygraph_mode() and in_dynamic_mode()

* [dygraph]unify _non_static_mode() in_dygraph_mode() and in_dynamic_mode()

* fixed cyclic reference that caused patial import

* fixed bad change

* fix bad import

* fix bad import

* fix bad import

* fix ut failed caused by change in_dynamic_mode

* fix ut failed caused by change in_dynamic_mode

* fixed usage of in_dynamic_mode() or in_dygraph_mode()

* revert python3 to python in .pre-commit-config.yaml

* fix merge conflicts

* [Eager] polish several ops

* rm useless code

* rm in_legacy_dygraph nn part1

* rm non_static_mode

* modify rrelu

* isort all files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* fix_docx_stanh

* fix einsum api en docs issue

* fix model api en docs issue

* for codestyle

* fix_einsum.py_einsum, test=document_fix

* fix_model.py_Model, test=ducument_fix

* fix_creation.py_meshgrid, test=document_fix

* fix_linalg.py_slogdet, test=document_fix

* fix_loss.py_SoftMarginLoss_CrossEntropyLoss_NLLLoss_BCELoss, test=document_fix

* norm.py_SyncBatchNorm, test=document-fix

* norm.py_SyncBatchNorm, test=document_fix

* norm.py_SyncBatchNorm, test=document_fix

* list18-30, test=document_fix

* refix_list1-15, test=document_fix

* deletefiles, test=document_fix

* fixedapi_pre-commit, test=document_fix

* fix_list31-45, test=document_fix

* list111, test=document_fix

* some_fix, test=document_fix

* some_fix, test=document_fix

* somefix, test=document_fix

* somefix, test=document_fix

* refix, test=document_fix

* refix, test=document_fix

* refix, test=document_fix

* refix, test=document_fix

* rerfix, test=document_fix
Co-authored-by: Ligoml <limengliu@tiaozhan.com>

* update config

* re-blacken python code

* temporarily disable date and diff_py_file

* skip a format

* move reduce_all_flag from python to c++

* fix infer shape bug

* fix bug;

* fix sum infer meta bug

* fix reduce sum grad gpu bug

* fix amin amax bug;

* add paddle.nn.functional.pairwise_distance (cattidea/Paddle#273)
* remove the test case for undefined behavior
Co-authored-by: NSigureMo <sigure.qaq@gmail.com>