* [CodeStyle] remove all future import

* revert test_error.py

* restore future import in example code

* add case where the HOME directory does not have write permissions

* add some notes

* 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

* fix image cv2 import

* fix lamb

* Support C++ import python on windows for paddle

* Support C++ import python on windows for paddle

* del py2 code2

* fix test timeout

* add progressbar for datasets downloading

* Add deprecated warning info.

* Add unittest for deprecated decorator.

* Add warning info for tensor.grad

add __all__=[] to python files not in API public list; import * only support in API public list files (#32643)

* fix DATA_HOME path in win

* lazy import for scipy

* rm unused check

* 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 '''

* Fix en doc for rnn.py. test=document_fix

* Delete mq2007 dataset.

* cat exeception in request download; test=develop

* add re-try in download; test=develop

* Remove dependency on nltk for paddle __init__.
test=develop

* Remove nltk.movie_reivew sentiment dataset to remove dependency on nltk.
test=develop

* remove paddle.readers API. test=develop

remove the dependence of matplotlib  in dataset of uci_housing

* Move hapi form paddle/incubate to paddle

* Remove vision/datasets/utils.py and clean code

* Add sample code for conll05

* Print pull path when saving model

* Fix sample code after paramter_list of SGD is changed to parameters

* Fix bug in wmt16 datase

* refine manual seed

* fix ci problem

* fix unittests

* fix unittest

* set is_init_py=false in manual_seed

* fix unittest

* fix bernoulli_op

* fix(unittest): change random_seed to manual_seed

* 🐞fix(unittest): fix manual_seed

* trigger ci

* fix test_sentiment

* fix test_imperative_save_load

* fix test_uniform_random_op

* fix test_uniform_random_op

* fix test_jit_save_load

* merge develop

* fix manual_seed

* fix manual_seed

* use global engine

* use shared_ptr

* fix double free

* fix bug

* fix bug

* fix bug

* fix test bug

* fix test bug

* fix test bug

* fix ci

* Make optimizer consistent in dygraph and static-graph and remove some LOG-INFO

* fix the compatiable problem between PY2 and PY3.

* add ut, test=develop

* add proxy, test=develop

* download dataset before test, test=develop

* change download log formate; test=develop

* add unittest for data download; test=develop

* remove cache before download; test=develop

replace mnist dataset url