Ignore installed package when using pip

If you have an error when you install python package using pip like this,

Cannot uninstall '~~~'. It is a distutils installed project and thus we cannot accurately determine which files belong to it which would lead to only a partial uninstall.

You can solve this problem by adding this option:

--ignore-installed

For example,

$ sudo pip install <package-name-to-install> --ignore-installed <package-name-get-error>