Undefined name: exception --> Exception
Undefined name: exception --> Exception

exception (lowercase 'e') is an undefined name in this context while Exception (uppercase 'e') is the superclass.

flake8 testing of https://github.com/cclauss/pythonparser on Python 2.7.14

$ flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics

./pythonparser/source.py:259:9: F821 undefined name 'exception'
        exception.__init__(self, "Ranges %s and %s overlap" % (repr(first), repr(second)))
        ^
1     F821 undefined name 'exception'
1
m-labs/pythonparser