* 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

* 1. add the python api grad 2. add final and intermediate state vlog 3. change the python_api error logic

* add python api or close the check_eager=True

* fix the compatibility

* matmul

* disable unittests: test_elementwise_add_op test_scatter_nd_op test_gather_nd_op test_scatter_op test_index_sample_op test_elementwise_add_mkldnn_op

Refactored python-level trace_op to call through _C_ops instead of Tracer::TraceOp, under eager_mode (#38338)

* Replaced core.ops with _C_ops

* Refactored python-level trace_op to call through _C_ops instead of Tracer::TraceOp, under eager_mode

* Modified trace_op interface

* Refactored trace_op logic for eager mode

* Added Eager Dygraph support for OpTest

* Fixed ci issues

* Fixed CI failures

* Fixed Coverage CI Issues

* Fixed XPU CI Issues

* Add digamma_op and unittest

* add digamma_op api

* remove special DigammaCudaKernel and correct some docs

* remove unused headers

* fix api doc error