* add parallel graph dist test=develop

* update test=develop

* update style test=develop

* Enable INT8 ReQuantize OP
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* Clean code
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* Add comments
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* Revert "Clean code"
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This reverts commit a7a49b8aa214f9730cb84e11ea96da564fe4b4d9.

* Modify requantize op test
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* fix requantize UT by moving public function to public test file.
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* Fix test fail due to file address change.
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* Change file address for requantize op.
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* refine recurrent_op
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* remove unnecessary code
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* In some case, the input may have one than one negative value.
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* fix matmul bug
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* remove the ignored from is_empty and less_than test=develop

* fix api spec test=develop

* fix the api spec test=develop

* test=develop

* add ir memory optimize test case for IfElse op, test=develop

* fix some unitttest failure by force using the python memory_optimize, test=develop

* tweak comments, test=develop

* fix unittest, test=develop

* fix unittest, test=develop

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test=develop

test=develop

* MKLDNN: Add UT for conv_transpose_mkldnn op.
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* MKLDNN: Add fuse_bias check UT for conv_transpose_mkldnn op.
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* Revert "Add Event for TensorCopy (#15953)"

This reverts commit 7235fd66.
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* fix CI
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* Update detection API add new check document

* update API.spec

* test=develop;add shanyi15 approved API.spec

* test=develop;update PM check API.spec

* check api.spec

* test=develop

* update API.spec

* test=develop;update API.spec

* update API.spec

* cat API.spec

* update documnent in api.spec

* check python35 api.spec

* update print_signatures md5 function

* test=develop

* update API.spec

* test=develop;fix python3 API.spec diff

* test=develop

* test=develop

* test=develop

* Unified ParallelExecutor and Compiler

Add Event for TensorCopy 

* fix image_resize annotation

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* fix some typo

* Update nn.py

* Update interpolate_op.cc

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