zero or one argument

[Skaperen]

ok, then i'm stuck with variable arguments.  i was wanting to do something like:

def myfun(myarg=None):
    if myarg is None:
        myarg='default'
    ...

myfun() # zero arguments OK
...
myfun('a string') # one argument OK
...
myfun('a string','an extra string') # two arguments so it should fail here