fix bugs: fix some bugs in loading data

[Hsiayukoo]

(1)use with open() rather than open() (2)use meaningful variables (3)fix some deep copy problems

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Motivation

修改了以下问题：

1. 参数意义不明确

2. open 之后没有关闭

3. 构造函数缺少传参，images_dir 地址拼写错误

4. 深浅拷贝问题 最后读取后的数据每一个标签都关联上了所有的样本。

Test Plan

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Related Issues and PRs

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