一.现象还原：
当新建.py文件时，需要引用selenium中的方法时，报错，提示红波浪线：
Unresolved reference 'selenium' less... (Ctrl+F1)
This inspection detects names that should resolve but don't. Due to dynamic dispatch and duck typing, this is possible in a limited but useful number of cases. Top-level and class-level items are supported better than instance items.
二.解决办法：
1.点击编辑器“File”->点击“settings”
2.在“settings”中，选择“Project：Pytest”->“Project Structre”->点击“Add Content Root”
3.找到安装selenium的路径，红色字体（例：F:软件python3.6.1Libsite-packages），最后点击【OK】
4.选择selenium包的路径，再点击“Sources”
5.最后再“Apply”应用，再返回.py文件中就不会再提示错误了。