title: Python pip error: "Cannot fetch index base URL https://pypi.python.org/simple/"
body: <p>I'm trying to install several packages using pip. When I do this using sudo, this error occurs: "Cannot fetch index base URL <a href="https://pypi.python.org/simple/" rel="noreferrer">https://pypi.python.org/simple/</a>". When I execute the command without sudo, the package downloads successfully, but I don't have enough permissions. What could be the reason for such different behaviour? I'm sitting behind a proxy.</p>