* 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

* auto parallel sharding base

* chmod

* add unitest

* set unitest cmake dist label

* revise code according to rewiew

* chmod

* bugfix for grad_clip and param broadcast

* chmod

* update unitest

* chmod

* add clip

* chmod

* add amp pass

* chmod

* add unitest

* remove grad update

* fixed bug

* fixed bug

* fixed typose

* fixed typoes

* auto parallel sharding base

* chmod

* add unitest

* set unitest cmake dist label

* revise code according to rewiew

* chmod