Minor improvements to the template code.
Minor improvements to the template code.

* Add comment bars segregating this code from the rest.
* Improve readability of the re pattern with indentation and comments on
  the same line.
* Replace the groupdict() and get() pair with a direct call to group()
  which does the same thing.

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