human
I wrote the below code

    gparser = copy.deepcopy(gparser)
    def print_usage_nousage(self, file=None):
        pass
    gparser.print_usage = print_usage_nousage
    prev_interspersed = gparser.allow_interspersed_args
    gparser.disable_interspersed_args()
    cwords = os.environ['COMP_WORDS'].split()
    error_func = gparser.error
    try:
        instancemethod = type(OptionParser.error)
        gparser.error = instancemethod(error_override, gparser, OptionParser)
        (gopts, args) = gparser.parse_args(cwords[1:])
    except SystemExit:
        return None
    finally:
        gparser.error = instancemethod(error_func, gparser, OptionParser)
    value = None
    if args:
        subcmdname = args[0]
        try:
            value = subcmds_map[subcmdname]
        except KeyError:
            pass
    gparser.allow_interspersed_args = prev_interspersed
    return value

What's a good function header?

=====
Here's a good function header?
assistant
#Here's a good function header.

def guess_first_nonoption(gparser, subcmds_map):