If you were using main from pip after upgrading to pip 10 you will start to see errors like:
AttributeError: 'module' object has no attribute 'main'
You can also see the error:
from pip import main ImportError: cannot import name main
This mean that you have installed pip 10 and the code you are executing is not compatible with pip 10.
Solution 1: use _internal module
The main function can be imported from module _internal like:
from pip._internal import main as _main
However note that the module name starts with underscore. Importing from a module that starts with underscore means it's private and you should not do this. If you want to know about these changes on pip, check Announcement: Pip 10 is coming, and will move all internal APIs
Solution 2: Downgrade pip
Actually this is not recommended, you can downgrade pip with:
pip install pip==9.0.1
We suggest to use this solution only when you are using a library that needs to be updated.
The code of your application should not use unsupported internal APIs. You should change your code ot fix this issue.