def METHOD_NAME(self) -> Any:
    """
    The checker created by the C{--auth} command-line option returns a
    L{Deferred} that fails with L{UnauthorizedLogin} when
    presented with credentials that are unknown to that checker.
    """
    self.options.parseOptions(["--auth", "file:" + self.filename])
    checker: FilePasswordDB = self.options["credCheckers"][-1]
    self.assertIsInstance(checker, FilePasswordDB)
    invalid = UsernamePassword(self.usernamePassword[0], b"fake")
    # Wrong password should raise error
    return self.assertFailure(
        checker.requestAvatarId(invalid), error.UnauthorizedLogin
    )