* fix stop_gradient in paddle.to_tensor

* make to_tensor copy if data is varbase

* add ut

* refine sample code

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 hang of hybrid parallel

* fix new_group for hang problem

* add seq_conv pbtxt

* add seq_conv pbtxt

* Dygraph Recompute support AMP

* dygraph recompute: update unitest

* add progressbar for datasets downloading

add an assertion to ensure that the size of each dim of the parameter to be created is larger than 0. (#33265)

* 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

* update mp

* fix path error on windows when precision switch is turn on

* fix error

* Update get_pr_ut.py

fix format error

* Update get_pr_ut.py

* add trt convert op: reshape

* reshape

* fix

* input: Shape,ShapeTensor

* Add some comments

* fix spawn default nprocs get error

* polish error message