code: def kalman_filter(points, noise):
      
      kalman = ikalman.filter(noise)
      for point in points:
          kalman.update_velocity2d(point.lat, point.lon, point.dt)
          (lat, lon) = kalman.get_lat_long()
          point.lat = lat
          point.lon = lon
      return points
docs: Smooths points with kalman filter
  
      See https://github.com/open-city/ikalman
  
      Args:
          points (:obj:`list` of :obj:`Point`): points to smooth
          noise (float): expected noise