解决问题
pandas\core\frame.py:2754: SettingWithCopyWarning:
A value is trying to be set on a copy of a slice from a DataFrame
解决思路
发生在pandas\core\frame.py文件内，
设置复制警告:：试图在DataFrame切片的副本上设置一个值。其实，这是Pandas的API改了使用方法。
请参阅文档中的警告：http://pandas.pydata.org/pandas-docs/stable/indexing.html#indexing-view-versus-copy
self._update_inplace (new_data)
解决方法
参考文章：成功解决SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame
https://blog.csdn.net/qq_41185868/article/details/88368669
