SF bug #1067018: Obsolete info in Tutorial 9.1
SF bug #1067018: Obsolete info in Tutorial 9.1

Removed a section that is out of date after type/class unification.
While there was still some validity, the paragraph offered more
confusion that insight.

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