def todays_count(address, response_type):
    """The number of responses sent to an address today.

        :param address: The address who is the recipient of the auto-response.
        :type address: `IAddress`
        :param response_type: The response type being sent.
        :type response_type: `Response`
        :return: The number of auto-responses already received by the user
            today, of this type, from this mailing list.
        :rtype: int
        """
