code: def movvar(x, windowsize=3, lag="lagged"):
      """moving window variance
  
  
      Parameters
      ----------
      x : ndarray
         time series data
      windsize : int
         window size
      lag : 'lagged', 'centered', or 'leading'
         location of window relative to current position
  
      Returns
      -------
      mk : ndarray
          moving variance, with same shape as x
  
  
      """
      m1 = movmoment(x, 1, windowsize=windowsize, lag=lag)
      m2 = movmoment(x, 2, windowsize=windowsize, lag=lag)
      return m2 - m1 * m1
  
file_path: statsmodels/statsmodels/sandbox/tsa/movstat.py
imports: import numpy
  from scipy import signal
  from numpy.testing import assert_array_equal, assert_array_almost_equal
label_desc: Use image node_id 5 for calling a global function with example usage: movvar(x, windowsize, lag) and returns: unknown