Weblate is a Web-based Python tool that can add translations to a project hosted and developed via Git. And yes, Weblate is GitHub friendly.
Developed to simplify translations for any kind of project, not just Python, Weblate provides an easy-to-use Web interface where administrators can create translations, add their text and have it automatically reflected in the Git structure.
Weblate uses Django's admin interface for the UI and provides many useful features, including a fine-grained permissions system, propagation of translations into Git branches and automatic merging of translation files, just to name a few.
Supported translation formats include Gettext, XLIFF, Java properties files, Qt Linguist, Android string resources, Apple OS X strings, .PO and all the formats from the translate-toolkit Python package.
Download Weblate from our Scripts section here.
Check out more Weblate screenshots here.