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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 set_sound_mode(self, sound_mode):
 """ Set sound_mode of device. Valid values depend on the device and should be taken from "sound_mode_list". Return "True" on success and "False" on fail. """

        if sound_mode == ALL_ZONE_STEREO:
            if self._set_all_zone_stereo(True):
                self._sound_mode_raw = ALL_ZONE_STEREO
                return True
            else:
                return False
        if self._sound_mode_raw == ALL_ZONE_STEREO:
            if not self._set_all_zone_stereo(False):
                return False
        # For selection of sound mode other names then at receiving sound modes
        # have to be used
        # Therefore source mapping is needed to get sound_mode
        # Create command URL and send command via HTTP GET
        command_url = self._urls.command_sel_sound_mode + sound_mode
        # sent command
        try:
            if self.send_get_command(command_url):
                self._sound_mode_raw = self._sound_mode_dict[sound_mode][0]
                return True
            else:
                return False
        except requests.exceptions.RequestException:
            _LOGGER.error("Connection error: sound mode function %s not set.",
                          sound_mode)
            return False