* isort all files

* revert conflicting files

* revert conflicting files

* revert conflicting files

* [CodeStyle][E711] use `is`/`is not` for comparison with `None`

* `self.assertTrue($A is None)` -> `self.assertIsNone($A)`

* `self.assertTrue($A is not None)` -> `self.assertIsNotNone($A)`

* `self.assertFalse($A is None)` -> `self.assertIsNotNone($A)`

* `self.assertEqual($A, None)` -> `self.assertIsNone($A)`

* `self.assertNotEqual($A, None)` -> `self.assertIsNotNone($A)`

* [CodeStyle][py2] remove `six` package (part2)

* six.ensure_str

* remove unused `import six`

* remove six from BUILTIN_LIKELY_MODULES

* remove six in example code

* remove some decode

* try to fix example code

* fix MockEtcdClient get/get_prefix returns data type

* fix MockEtcdClient get_prefix returns data

* fix MockEtcdClient get returns data

* remove `six` in pypi and conda requirements

* fix MockEtcdClient add_watch_callback/add_watch_prefix_callback returns data type

* refine MockEtcdClient

* [CodeStyle][black] format dy2static unittests

* format some missing files

* update lineno in test_origin_info

* update lineno in test_error

* update lineno

* trim trailing whitespace

* fix `.cmake-format.py`

* revert npu ut changes, avoid npu ci error

* update conda build script for cuda11

* update conda build script

* modified wheel name

* update conda_build

* fix error

* add cudnn8.1 for cuda11.2

* fix format error

* test=develop, rm pathlib

* update conda_build script with removing opencv

* modified filepath

* modified some content

* Delete Commented-Out Code

* delete prettytable in conda_build
Co-authored-by: NXieYunshen <1084314248@qq.com>

* upgrade comment string to raw string

* fix string in

* fix string with ' '

* revert update on comments

* upgrade only necessary

* fix sample code checker

* fix comments with '''

* add script for conda package build