Implication Detection isn't (Quite) Perfect

e.g. doesn't know that 'x is None' implies 'not x’
- (So, if one rule uses 'x is None' and one uses 'not x', they will conflict when both apply)
Currently knows about:
- Class relationships (isinstance/issubclass)
- Comparison operators (<,>, ==, !=, etc.)
- Logical operators (and, or, not)

e.g. doesn't know that 'x is None' implies 'not x’