From: @alexyuyue
Reviewed-by: 
Signed-off-by:

From: @yuan_shen_zhou
Reviewed-by: @liangchenghui
Signed-off-by: @liangchenghui

From: @liubuyu
Reviewed-by: 
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From: @liangzhibo
Reviewed-by: 
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From: @xiefangqi
Reviewed-by: @liucunwei,@heleiwang
Signed-off-by: @liucunwei

From: @luoyang42
Reviewed-by: 
Signed-off-by:

From: @lijiaqi0612
Reviewed-by: @kingxian,@zh_qh
Signed-off-by: @kingxian

Signed-off-by: alex-yuyue <yue.yu1@huawei.com>

From: @lijiaqi0612
Reviewed-by: 
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From: @hfarahat
Reviewed-by: 
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From: @heleiwang
Reviewed-by: @liucunwei
Signed-off-by: @liucunwei

From: @lixiachen
Reviewed-by: 
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From: @zhangbuxue
Reviewed-by: 
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From: @xulei2020
Reviewed-by: @pandoublefeng,@liucunwei
Signed-off-by: @pandoublefeng

From: @luoyang42
Reviewed-by: 
Signed-off-by:

From: @zhangbuxue
Reviewed-by: 
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From: @jiangzg001
Reviewed-by: @liangchenghui,@c_34
Signed-off-by: @liangchenghui

1. description of num_shard in datasets.py
2. add param validation for sampler
3. add description for add_child in sampler.py

fix c++ ut compilation failed of Asan bug

From: @lixiachen
Reviewed-by: 
Signed-off-by:

Fix can not collect input data when batch size is 1 and total step
number is 1

Fixed spelling errors

From: @jiangzg001
Reviewed-by: @liangchenghui
Signed-off-by: @liangchenghui

From: @david-he91
Reviewed-by: 
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From: @Somnus2020
Reviewed-by: 
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From: @alexyuyue
Reviewed-by: 
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From: @mhmotallebi
Reviewed-by: 
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From: @yangzhenzhang
Reviewed-by: @kisnwang,@stsuteng
Signed-off-by: @stsuteng

From: @zhangbuxue
Reviewed-by: @ginfung,@zh_qh,@ginfung
Signed-off-by: @ginfung