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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 cmd_changealt(self, args):
        '''change target altitude'''
        if len(args) < 1:
            print("usage: changealt <relaltitude>")
            return
        relalt = float(args[0])
        self.master.mav.mission_item_send(self.settings.target_system,
                                          self.settings.target_component,
                                          0,
                                          3,
                                          mavutil.mavlink.MAV_CMD_NAV_WAYPOINT,
                                          3, 1, 0, 0, 0, 0,
                                          0, 0, relalt)
        print("Sent change altitude command for %.1f meters" % relalt)