As this page says:
After inserting this package in your editor's python path, you will get autocompletion for every PyGObject module! By default the package is saved in ~/.cache/fakegir/. This is the directory you want to add to your Python PATH. Of course, you shouldn't put this package in your global PYTHONPATH or your PyGObject applications will stop working immediatly
How do I achieve this with Sublime Text?