The telegram/ext directory is getting a bit crowded. It would be good if all _*handler.py files as well as filters.py (which is part of the handlers setup) would be moved to a directory telegram/ext/_handlers. The imports and telegram/ext/__init__.py would have to be adapted in such a way that the public API doesn't change, i.e. from telegram.ext import BaseHandler, CommandHandler, filters etc is still the expected way of importing.