How to install GExiv2 on a virtualenv?

First of all setup GExiv2 on your system installing it the usual way, for example with apt-get. Now you have two ways to get it working on a virtualenv. The first is create your virtualenv starting from system packages. The `--system-site-packages` option links the public packages installed on the system to the new virtual environment. The second one is to symlink the GExiv2 library from your virtualenv with:

$ cd virtualenv
$ cd lib/python2.7/
$ ln -s /usr/lib/python2.7/dist-packages/gi