* support type hint

* fix unittest

* transform complex scale to tensor

* add test_case for complex scalar

* modify import paddle

* Combine amp and qat
* add unit test

* del py2 code2

* fix test timeout

* support non-tensor type

* fix unittest failed

* add unittest with prune

* rm unused code

* coverage

* fix two or

* Support append customize attributes into op_desc in nn.Layer

* fix code style

* support override

* add unittest

* Modify into core.ops.run_program

* add DDout in core.ops.run_program

* fix typo

* add DOut

* fix typo

* put DOut last

* modify API nn.Bilinear's doc, test=develop

* move data to CUDAPlace in advance

This PR made these changes to support double grad:

1. Translate `paddle.grad` to `paddle.static.gradients` to support double grad for dy2stat.
2. Fix IfElseTransformer bug which may not change value if "Store before Load" variable is in "Store" statement is in IfElse conditional statement
3. Add `DOut` to support double grad variables in `run_program_op`
4. Add support for renaming for double grads for `jit.save/load`

* fix the bug of div operation result using scale method do not exactly equal the result of elementwise_div method

* remove __div__ , __rdiv__ methods which do not define in python3

* modify the note

* add test case

* add test case

* Support convert sublayers in Sequential Container

* remove paddle.jit.set_code_level

* BugFix StaticAanlysis with gast.Subscript

* remove codes

* Add param_guard in ParameterList to support @to_static

* Refactor param_guard of @to_static

* fix unittest failed

* add more unittest

* add varbasecopy func to fix the paraBase type bug in layers.to API

* overload _copy_to func for ParamBase

* add xpuplace

* add waiting varbsecopy completion when not blocking

* fix dst_device bug

* modify varbase to shared_ptr

* fix find_unused_parameters default value

* Add deprecated warning info.

* Add unittest for deprecated decorator.

* Add warning info for tensor.grad

Dy2stat failed when user writes return paddle.to_tensor(xxx), the reason is that visit_Expr doesn't work when the Expr is in return. Some other statements may trigger same bug. To fix it, we re-wrote a transformer to transform paddle.to_tensor to paddle.assign for all Call nodes.

* add relu6_ hardsigmoid_ leaky_relu_ Inplace APIs

* add softmax_with_cross_entropy_ Inplace API

* add clip_ scale_ add_ subtract_ Inplace APIs

* add wlist

* fix parameter of scale api

* add add_n_ Inplace API and remove log_ Inplace API

* fix elementwise_add_ and elementwise_sub_ broadcast problem

* elementwise inplace api give error message before run the op

* use broadcast_shape in elementwise inplace op

* add 8 inplace apis that is auto generated

* add unittest for all inplace apis

* add decorator for inplace apis in static mode

* fix windows blas fail of exp inplace api, change array_equal to allclose

* add flatten inplace api

* add flatten unittest

* fix flatten unittest

* add decorator

* fix grad.numpy in test_pylayer_op

* unsupport softmax_with_cross_entropy_

* add test_inplace_softmax_with_cross_entropy to static_mode_white_list

* delete __all__ in inplace_utils

* delete activation inplace function and add Tensor.inplace_func

* change paddle.inplace_ to Tensor.inplace_

* fix little problem

* add paddle in inplace_utils

* jit.save/load support function.

* delete unnittest test_jit_load_model_incomplete.

* edit code according to CI

* Modify the documentation.

* add note to doc.

* Modified params of some APIs to support tuple and list.

* fixed bug.

* Modified the return value of tensor.grad from numpy as tensor.

* Modify unittests.

* fixed bugs.

* Add warning info for x.grad

* fixed unittests which used x.grad

* fixed bug.

* Unset ReserveSpace for inference program.

* Support training from an inference program.

* add clip/check

* add amp & clip grad in dygraph

* add logging

* support dp & mp

* fix sublayer error with include_sublayers=False

* add ut

* refactor include_sublayers related api

* fix ut

* fix ut of transformer

* fix ut of transformer

* remove useless code

* change sublayer api

* polish code

* add test for include_self=True

* add layer.to api

* add layer.to api

* add layer.to api

* add the doc for Layer.to

* add input type checking

* modify assert and import bug

* format code style

* format code style

* make place support str type

* add SetGradVarBase method to set the gradient after conversion

* modify argument palce to device

* modify argument palce to device

* modify doc of layers.to API

* add xpuplace to device argument

* fix undefind var in For

* fix code style

* support DictCmp and zip grammar

* fix code style