Python runs unittest as a package import error, attributeerror: module unittest has no attribute main‘

It didn't work for a long time python 了 , Use today python I made a very low-level mistake when writing test code , I'd better post it , Warn yourself not to make mistakes next time ！

Source code ：

Error report after operation module ‘unittest’ has no attribute ‘main’

The reason for the error ：
unittest Can't find mian attribute , I've been looking for mistakes for a long time , I found that my package name was written as unittest, This leads to import This package is imported , Instead of testing the framework

modify ：
Change the package name to something else , The code doesn't need to be modified