Returns a list of device objects that match the serial number
            in param 'sn'.

            This will match partial serial numbers.

def search_for_devices_by_serial_number(self, sn):
        """
            Returns a list of device objects that match the serial number
            in param 'sn'.

            This will match partial serial numbers.
        """
        import re

        sn_search = re.compile(sn)

        matches = []
        for dev_o in self.get_all_devices_in_portal():
            # print("Checking {0}".format(dev_o['sn']))
            try:
                if sn_search.match(dev_o['sn']):

                    matches.append(dev_o)
            except TypeError as err:
                print("Problem checking device {!r}: {!r}".format(
                                    dev_o['info']['description']['name'],
                                    str(err)))
        return matches