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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def decode_kempressed(bytestring):
 """subvol not bytestring since numpy conversion is done inside fpzip extension."""

  subvol = fpzip.decompress(bytestring, order='F')
  return np.swapaxes(subvol, 3,2) - 2.0