Traceback (most recent call last):
File "./prog.py", line 8, in <module>
File "./prog.py", line 5, in inverter
File "./prog.py", line 5, in inverter
File "./prog.py", line 5, in inverter
[Previous line repeated 995 more times]
File "./prog.py", line 2, in inverter
RecursionError: maximum recursion depth exceeded while calling a Python object