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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 __callback (self, scan):
        '''
        Callback function to receive and save Laser Scans. 

        @param scan: ROS LaserScan received
        
        @type scan: LaserScan

        '''
        laser = laserScan2LaserData(scan)

        self.lock.acquire()
        self.data = laser
        self.lock.release()