* update config

* re-blacken python code

* temporarily disable date and diff_py_file

* skip a format

* [CodeStyle] remove all future import

* revert test_error.py

* restore future import in example code

* use yapf to format all python file

* yapf exclude two unittests file for they rely on writing and reading file, and format will break them

* disable diff_py_file because too many diff files cause command following failed

* fix failed tests in yingchun gived list

* add unittests into static_mode_white_list

* add enable static

* fix dist unittest

* skip test_sigmoid_focal_loss_op & add gym

* revert no need skip unittests

* remove gym

just skip case of distribute on windows

* add to_readable_code method, test=develop

* polish doc details, test=develop

* polish doc note, test=develop

* fix unittest error, test=develop

* fix coverage, test=develop

* add print test, test=develop

* add print param, test=develop

* hidden to_readable_code api, test=develop

* remove original tool methods, test=develop

* remove old api using code, test=develop