This addresses issues with offline builds - due to pip latest version checking Source archive downloaded from https://pypi.python.org/packages/source/v/virtualenv/virtualenv-12.0.5.tar.gz and uncompressed into python/virtualenv. The egg-info directory was removed.
virtualenv
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.. image:: https://pypip.in/v/virtualenv/badge.png
:target: https://pypi.python.org/pypi/virtualenv
.. image:: https://secure.travis-ci.org/pypa/virtualenv.png?branch=develop
:target: http://travis-ci.org/pypa/virtualenv
For documentation, see https://virtualenv.pypa.io/