Lots of cosmetic changes. Lots of small bugfixes (lint!). Made bgn_group and end_group form methods instead of top-level functions.
Lots of cosmetic changes.
Lots of small bugfixes (lint!).
Made bgn_group and end_group form methods instead of top-level functions.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator