Pip doesn't install latest available version from pypi (argparse in this case)

Question

The problem

I worked on some python projects lately and had lots of problems with pip not installing the latest versions of some requirements. I am on

Answer 1

Here's the command I used to install argparse using pip 1.5.4:

pip install --allow-all-external argparse==1.2.1

Answer 2

I think this line is the key:

Some externally hosted files were ignored (use --allow-external to allow).

When I install argparse here I get

You are installing an externally hosted file. Future versions of pip will default to disallowing externally hosted files.

Downloading argparse-1.2.1.tar.gz (69kB): 69kB downloaded

So you have a newer version of pip that is disallowing externally hosted files by default