code: 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(f __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()
docs: Callback function to receive and save Laser Scans. 
  
          @param scan: ROS LaserScan received
          
          @type scan: LaserScan