* add prim erf grad

* add yaml config for prim erf grad

* add math.h

* add cmath

* add math  defines

* use define math

* use define math

* define M_2_SQRTPI

* M_2_SQRTPI math

* try math.h

* fix typro

* remove pow in erf grad

* use new optest

* add fp16 fp32 test

* remove fp16 test

* update erf gumbel_softmax ..ops

* lint

* reset sequence_conv

* reset exponetial&interp nearest

* isort all files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* remove apis in fluid.ops

* fix test_activation_nn_grad

* fix circle import error

* fix ops

* fix cos

* fix divide not inplace

* remove lazy-import part

* 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

[CodeStyle][NPU] use np.testing.assert_allclose instead of self.assertTrue(np.allclose(...)) (part 1) (#44988)

* autofix

* try resolve precision issues

* revert some changes

* clean some `err_msg`

* 0.0001 -> 1e-4

* update commented assert code

* try to fix some shape errors

* `numpy` -> `np`

* empty commit, trigger kunlun ci, test=kunlun

* empty commit, retrigger kunlun ci, test=kunlun

* empty commit, trigger kunlun ci, try fix npu memcpy_h2d, test=kunlun

* try fix npu import error, test=kunlun

* 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

* Rename `Input` into `InputSpec`

* remove alias

* add erf op and python interface.

* add fp16 support for erf op.

* add unitests for erf op and its python interface.

    Add a python interface for Gelu.
    Add documentation for fluid.layers.gelu.