* polish parallel api impl & doc details

* add unittest for coverage

* remove spawn test in py2.7

* add parallel api into white list

As the title

* add soft_label and axis for CrossEntropyLoss and improve performance,test=develop

* fix conflict in nn/functional/loss.py, test=develop

* fix some docs test=develop;test=document_fix

* add code example test=develop;test=document_fix

* fix code example test=develop;test=document_fix

* fix code example test=develop;test=document_fix

* fix code example test=develop;test=document_fix

* fix clip by norm eng doc. test=develop

Add support for using tuple as tensor.shape (For example: a, b, c, d = x.shape)

* add lamb optimizer and unittest

* fix lamb

* fix lamb v2 op

* fix sampling id

* fix lamb sample code

* Update lamb.py

* fix doc

* fix doc

* Update lamb.py

* 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 '''

[Dynamic-to-Static] Fix bug of convert_logical_and/convert_logical_or: the operands are executed sequentially(#28993)

  
  1) The operands are executed sequentially according to the running logic of Python.
  
  2) If the left hand operand is True(for convert_logical_or)/False(for convert_logical_and), the right hand operand should be executed.

The PR description is long. See details in the PR link.

* fix eng doc, test=develop

* add import deprecated for layers, test=develop

* add block line for doc generate, test=develop

* remove todo for create_variable, test=develop

* add blank line for doc generate, test=develop

* add blank line for doc generate, test=develop

* polish dataloader doc detail, test=decument_fix

* fix commnet error

* fix word error

* update, test=develop

* fix English doc for dice_loss, log_loss, unfold and NLLLoss API test=document_fix

* ps gpu transpile

* ps gpu

* remove op

* gps trainer

* local ps

* add macro

* HeterBox

* def cuda

* tab

* code style

* style

Co-authored-by: Thunderbrook <a754913769#163.com>

* refactor momentum op to combine weight_decay (scale op and sum op)

fix error for Can not find test to add properties to:test_parallel_dygraph_transformer,test_parallel_dygraph_sparse_embedding (#28968)

* fix conv_transpose unittest. test=develop

* fix dataloader. test=develop

* fix param base trainable set failed

* add unittest

* fix typo

* polish comment

Adding uint8 support for squeeze operator.

* fix code example, test=document_fix

* Add bf16 matmul, fc, elementwise add and mul

* Correct unit test

* Fix wrong out dtype from helper.input_dtype

* add unittest

* remove disable_static in op_test

* fix param name typo

* 1.add xpu slice op 2. add xpu top_k op 3.modify xpu cast to new api

* 1.add xpu slice op 2. add xpu top_k op 3.modify xpu cast to new api

* add lstm, simple rnn op kernel

* fix the test_lstm for the rnn op

* change func name

* fix forward postprocess bug

* add gru forward, backward code

* remove unittest.skipIf; use a big rnn op instead of combination op

* fix input doesn't have gradient bug

* add eigen lstm forward, backward
Co-authored-by: Nwawltor <fangzeyang0904@hotmail.com>

* adjust kunlun header file
*test=kunlun

* update kunlun unittest
*test=kunlun

* update xpu unitest
* test = kunlun

* update xpu unittest
* test=kunlun

* update xpu unitest
* test=kunlun

[Dynamic-to-Static] Fix bug in loop_transformer: loop vars should contain the var from ancestor-for-node (#28735)