Fix typo in comment
Refactor base class representation to be Node

This is needed for namedtuple in base class list.

Still not working!
Fix type checking
Fix semantic analysis
Fix semantic analysis of namedtuple in base class list
Fix source pretty printing of class defs
Add NamedTuple test case
Add NamedTuple test case
Refactor named tuple test cases
Fix type checking with named tuple as base class
Add test case
Add test case for Tuple[...] as base class
Update test cases
Add test case
Add test case
Merge branch 'namedtuple-baseclass'
Add Python 2 NamedTuple support
Fixes to complex in Python 2
Suuport shorthand namedtuple field syntax
Add test case