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

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: 
Signed-off-by:

From: @Somnus2020
Reviewed-by: 
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From: @alexyuyue
Reviewed-by: 
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From: @mhmotallebi
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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

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

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

From: @zichun_ye
Reviewed-by: @wang_zi_dong,@sunnybeike
Signed-off-by:

fix typo in probability module

fix pylint in msp

From: @yuchaojie
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From: @tina_mengting_zhang
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From: @lijiaqi0612
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From: @yanglf1121
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From: @alexyuyue
Reviewed-by: 
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Signed-off-by: alex-yuyue <yue.yu1@huawei.com>

From: @zhangbuxue
Reviewed-by: 
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From: @Somnus2020
Reviewed-by: 
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From: @lijiaqi0612
Reviewed-by: 
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with comments from the peer view addressed