Exit Python Shell

Hans Nowak writes about how python interactive shell should quit/exit
when you type 'quit' or 'exit'.
He also shows an example.

>>> class _Exit:
...     def __repr__(self):
...         raise SystemExit
...
>>> exit = _Exit()
>>> exit # exits the interpreter

Stewart Midwinter comments how he modify it a bit and put them
into the site.py

def setquit():
  __builtin__.quit = __builtin__.exit = exit = _Exit()