code: def windowdiff(seg1, seg2, k, boundary="1", weighted=False):
      """
      Compute the windowdiff score for a pair of segmentations.  A
      segmentation is any sequence over a vocabulary of two items
      (e.g. "0", "1"), where the specified boundary value is used to
      mark the edge of a segmentation.
  
          >>> s1 = "000100000010"
          >>> s2 = "000010000100"
          >>> s3 = "100000010000"
          >>> '%.2f' % windowdiff(s1, s1, 3)
          '0.00'
          >>> '%.2f' % windowdiff(s1, s2, 3)
          '0.30'
          >>> '%.2f' % windowdiff(s2, s3, 3)
          '0.80'
  
      :param seg1: a segmentation
      :type seg1: str or list
      :param seg2: a segmentation
      :type seg2: str or list
      :param k: window width
      :type k: int
      :param boundary: boundary value
      :type boundary: str or int or bool
      :param weighted: use the weighted variant of windowdiff
      :type weighted: boolean
      :rtype: float
      """
  
      if len(seg1) != len(seg2):
          raise ValueError("Segmentations have unequal length")
      if k > len(seg1):
          raise ValueError(
              "Window width k should be smaller or equal than segmentation lengths"
          )
      wd = 0
      for i in range(len(seg1) - k + 1):
          ndiff = abs(
              seg1[i : i + k].count(boundary)
              - seg2[i : i + k].count(boundary)
          )
          if weighted:
              wd += ndiff
          else:
              wd += min(1, ndiff)
      return wd / (len(seg1) - k + 1.0)
  
label_desc: Use image node_id 1 for calling a global function with example usage: windowdiff(seg1, seg2, k, boundary, weighted) and returns: unknown