Autogenerated PyCharm files and virtual environments

I'm working on a plugin for setuptools that autogenerates .idea files for PyCharm projects. My code is based off of a plugin that is provided by PyBuilder (https://github.com/pybuilder/pybuilder/blob/master/src/main/python/pybuilder/plugins/python/pycharm_plugin.py).

The workflow that I'm trying to achieve is this:

$ git clone project

$ cd project

$ python setup.py pycharm

$ charm .

And then be in a project that is ready to be worked on. While I can get most of this working (correctly picking up my source, test, and excluded directories), I'm having trouble getting PyCharm to import my virtual environment. If I place this line in my .idea/project.iml file:

<orderEntry type="jdk" jdkName="Python 2.7.13 virtualenv at /Users/ewhauser/working/project/.tox/py27" jdkType="Python SDK" />

PyCharm won't recognize it as a venv unless it's already be imported as one before via the GUI. Is there any way to do this programmatically? Alternative way of achieving that workflow?

Thanks.