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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 of the linear operator. Note that this implementation uses an approximation that is only valid for small displacements. """

        # TODO allow users to select what method to use here.
        div_op = Divergence(domain=self.displacement.space, method='forward',
                            pad_mode='symmetric')
        jacobian_det = self.domain.element(
            np.exp(-div_op(self.displacement)))

        return jacobian_det * self.inverse