code: def _mathPolarDecomposeInterpolationTransformation(matrix1, matrix2, value):
      
      off, scl, rot = MathTransform(matrix1).decompose()
      m1 = ShallowTransform(off, scl, rot)
      off, scl, rot = MathTransform(matrix2).decompose()
      m2 = ShallowTransform(off, scl, rot)
      m3 = m1 + value * (m2-m1)
      m3 = MathTransform().compose(m3.offset, m3.scale, m3.rotation)
      return tuple(m3)
docs: Interpolation with ShallowTransfor, wrapped by decompose / compose actions.