Merge pull request !1033 from chujinjin/fix_addn_in_pynative_mode

Merge pull request !1023 from lichen/add_gatherv2_distributed_op

Merge pull request !920 from wsc/lossscale_script

Merge pull request !906 from yangyongjie/master

only reuse parameter from tensor when different session

Merge pull request !1043 from zhangzheng/simple

Merge pull request !1013 from YuJianfeng/master

Merge pull request !1036 from zhaozhenlong/fix-issue-assignsub

Merge pull request !977 from yao_yf/reshape_auto_parallel_strategy_search

Merge pull request !1037 from limingqi107/master

Merge pull request !1031 from amongo/ValueTupleOfNestedGraph

Merge pull request !1024 from jiangjinsheng/nn_example

Merge pull request !1003 from caojian05/mindspore_master_bugfix

Merge pull request !1025 from xulei/filter_op

Merge pull request !1016 from gengdongjie/master

Merge pull request !1001 from zhaozhenlong/conv2d-bp-input-grad-output-3

transform valuetuple to maketuple of graphs

add testcase

Merge pull request !967 from panyifeng/switch_case_primitive

Merge pull request !1011 from ghzl/improve-comment-enable-dump-context

Merge pull request !901 from rick_sanchez/master

Merge pull request !1018 from JichenZhao/globalbn_reshape_fix

Merge pull request !1020 from yoonlee666/master-readme

ImageGradients make compile check before others

Merge pull request !958 from yangzhenzhang/add_parallel_mode_for_cell

Merge pull request !987 from yangruoqi713/master