pip download library, problems

Error type 1: AttributeError:'Requirement' object has no attribute'project_name'

Cause of error: The library to be installed already exists in the environment

Solution: pip uninstall *** (uninstall the version library in the environment)

                  pip install *** (download the corresponding version library)

https://blog.csdn.net/blueheart20/article/details/52553984

 

 

Error type two: TypeError: unsupported operand type(s) for -=:'Retry' and'int'

Cause of error: There is a problem with the mirror source

Solution: Method 1: pip package management upgrade

                   pip install --upgrade pip

                   Method 2: Replace the domestic mirror source

https://mp.csdn.net/postedit/89527527