Merge pull request !3846 from liuxiao93/Add-ops-SeluSquaredDifference

Merge pull request !3821 from ZhangQinghua/master1

Merge pull request !3103 from yihuaijie/dev

Merge pull request !3880 from wangqiuliang/fix-gradients-issue-in-pynative

Merge pull request !3820 from zhangbuxue/support_dtype_and_shape_as_attr_in_graph_mode

Merge pull request !3473 from vlne-v1/change_base_class_of_parameter

Merge pull request !3744 from Xiaoda/14-add-new-graph-operations-in-auto-parallel

Merge pull request !3837 from liucunwei/add_test_for_mindrecord3

Merge pull request !3814 from liucunwei/enhance_map_file_for_imagenet

Added Distributed sampler option

Fix style

Merge pull request !3549 from anthonyaje/device_augment_mapop_refactor1

Merge pull request !3553 from tony_liu2/staging

Merge pull request !3739 from laiyongqiang/eliminate_memcpy_bug

Merge pull request !3119 from dengyutao/remove_blockreader

Merge pull request !3537 from riemann_penn/add_sparse_operator

Merge pull request !3727 from xiefangqi/fuzz_issue_pad_01

Merge pull request !3645 from chenzhongming/master

Merge pull request !3671 from ms_yan/vgg_optimize

add mindspore.hub and change model_zoo

Merge pull request !3657 from yangzhenzhang/add-stridedslice-op

Merge pull request !3405 from gziyan/fix_optimizer_parallel

fix line lengths

fix spacing

reverse a few changes

Merge pull request !3574 from hewei/rename_user_data_func

Merge pull request !3603 from jiangzhiwen/fix_column_names_exceeded

Merge pull request !3620 from 张学同/to_merge

Merge pull request !3612 from changzherui/mod_case

Refactored MapOp to in preparation to support device augment

Minor fix