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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 adjoint(self):
 """Adjoint wavelet transform. Returns ------- adjoint : `WaveletTransformInverse` If the transform is orthogonal, the adjoint is the inverse. Raises ------ OpNotImplementedError if `is_orthogonal` is ``False`` """

        if self.is_orthogonal:
            scale = 1 / self.domain.partition.cell_volume
            return scale * self.inverse
        else:
            # TODO: put adjoint here
            return super(WaveletTransform, self).adjoint