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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def expander_to_zone(self, address, channel, panel_type=ADEMCO):
 """ Convert an address and channel into a zone number. :param address: expander address :type address: int :param channel: channel :type channel: int :returns: zone number associated with an address and channel """


        zone = -1

        if panel_type == ADEMCO:
            # TODO: This is going to need to be reworked to support the larger
            #       panels without fixed addressing on the expanders.

            idx = address - 7   # Expanders start at address 7.
            zone = address + channel + (idx * 7) + 1

        elif panel_type == DSC:
            zone = (address * 8) + channel

        return zone