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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 land(self, absolute_height_m, duration_s, group_mask=ALL_GROUPS):
 """ vertical land from current x-y position to given height :param absolute_height_m: absolut (m) :param duration_s: time it should take until target height is reached (s) :param group_mask: mask for which CFs this should apply to """

        self._send_packet(struct.pack('<BBff',
                                      self.COMMAND_LAND,
                                      group_mask,
                                      absolute_height_m,
                                      duration_s))