* add up34

* modify var name in loop

* revert changes in test_slice

* Revert "modify var name in loop"

This reverts commit 6d748e371afb417054ed0c6b36fd11e87959a90d.

* temporarily ignore test_slice.py

* add comment

* empty commit, re-trigger all ci

* fix inc

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Co-authored-by: NSigureMo <sigure.qaq@gmail.com>

* delete old dygraph op test

* update config

* re-blacken python code

* temporarily disable date and diff_py_file

* skip a format

* [CodeStyle] remove all future import

* revert test_error.py

* restore future import in example code

* add yaml and unittest

* update yaml

* update backward yaml and unittest

* update yaml

* add Yolov3LossGradInferMeta

* update yolov3_loss_op.cc

* fix bug

* code format

* 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

* alias yolo_loss & decode_yolo_box to paddle.vision. test=develop

* add scale_x_y for yolo_box, test=develop

* refine eps in iou_similarity, test=develop

* polish the label_smooth

test=develop

* polish code

test=develop