Change parameter of the callback function.

        :param *args, **kwargs: parameter(s) to use when executing the
         callback function.

def useThis(self, *args, **kwargs):
        """
        Change parameter of the callback function.

        :param *args, **kwargs: parameter(s) to use when executing the
         callback function.
        """
        self._callback = functools.partial(self._callback, *args, **kwargs)