“5d98b6f217f8c59ae32f7dabefb69037d80f9cb2”上不存在“paddle/legacy/gserver/tests/test_LayerGrad.cpp”
* 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