code: def bytes(xyz):
      """Size of track in bytes.
  
      Parameters
      ----------
      xyz : array-like shape (N,3)
         Array representing x,y,z of N points in a track.
  
      Returns
      -------
      b : int
          Number of bytes.
  
      """
      return xyz.nbytes
  
imports: from dipy.utils.deprecator import deprecate_with_version
  from dipy.tracking.streamline import set_number_of_points
  import numpy
  from scipy.interpolate import splprep, splev
label_desc: Use image node_id 3 for calling a global function with example usage: bytes(xyz) and returns: xyz