def do_AUTHENTICATE(self, tag, args):
        args = args.upper().strip()
        if self.challengers not in args:
            self.sendNegativeResponse(tag, 'AUTHENTICATE method unsupported')
        else:
            self.authenticate(self.challengers[args](), tag)
dataset/ETHPy150Open nlloyd/SubliminalCollaborator/libs/twisted/mail/imap4.py/IMAP4Server.do_AUTHENTICATE/swapped operands of `not in`