My command either takes two positional arguments (in which case, both are required):
$ command foo bar or the name of a config file (in which case, the positional arguments are forbidden): $ command --config file How can I represent this with argparse; add_mutually_exclusive_group() isn't quite the right thing. It could specify that foo and --config are mutually exclusive, but not (as far as I can see) the more complicated logic described above. -- http://mail.python.org/mailman/listinfo/python-list
