* update readme test=document_fix

* fix api docs bugs test=document_fix

* support test_create_paramter

* support fused_transformer_encoder_layer

* skip program_desc tracer related tests in eager mode

* fix ci tests on eager

* add new API: paddle.clone;Tensor.element_size;nn.utils.parameters_to_vector

* fix comment

* update 2.0 public api in all left files

* reverse device.py all list;
fix some flake8 errors

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

* update 2.0 public api in nn

* replace Chinese character cause error in ci;synchronization with pr:#32588 to avoid 'ascii' codec in python2

* numbers used in paddle.nn.functional.norm but not imported

* fix code bugs

* fix code bugs test=document_fix

* fix code bugs test=document_fix

* fix examples, test=document_fix

* fix, test=document_fix

As the title

* 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 2.0api, test=develop

* fix, test=develop

* add weight_norm, test=develop