Return alias for device name if found.

        :param argin: The device name
        :type: tango.DevString
        :return: The alias found
        :rtype: tango.DevString

def DbGetDeviceAlias(self, argin):
        """ Return alias for device name if found.

        :param argin: The device name
        :type: tango.DevString
        :return: The alias found
        :rtype: tango.DevString """
        self._log.debug("In DbGetDeviceAlias()")
        ret, dev_name, dfm = check_device_name(argin)
        if not ret:
            th_exc(DB_IncorrectDeviceName,
                  "device name (" + argin + ") syntax error (should be [tango:][//instance/]domain/family/member)",
                  "DataBase::DbGetDeviceAlias()")

        return self.db.get_device_alias(dev_name)