Virtualenv doesn't install with the right python

[m2bright]

We have a scenario where:

1. We have system python, and then an installed python, different from the system python
   System - 2.7.6
   Custom - 2.7.10 - /usr/local/lib/python2.7.10
2. We have installed a virtualenv executable in the python2.7.10 version
3. When running python::virtualenv we do:
   python::python_virtualenvs: "/tmp/myVirtualEnv": owner: "www-data" group: "www-data" virtualenv: '/usr/local/lib/python2.7.10/bin/virtualenv'

Problem: When python executes, the virtualenv is created, but the python it is cloned from is the system python. The $version can't overcome it.