How do I know if arg1 is a single type (like a number), or a list?
isinstance is probably good enough for your needs.
if isinstance(arg1, (list, tuple, dict)): print "arg1 is a container" else: print "arg1 is (probably) not a container"
-- Brian Beck Adventurer of the First Order -- http://mail.python.org/mailman/listinfo/python-list