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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 _add_device(self, scs_id, ha_id, name):
 """ Add device to the list of known ones """

        if scs_id in self._devices:
            return

        self._devices[scs_id] = {
            'name': name,
            'ha_id': ha_id
        }