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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 voigt(self):
 """ Returns the tensor in Voigt notation """

        v_matrix = np.zeros(self._vscale.shape, dtype=self.dtype)
        this_voigt_map = self.get_voigt_dict(self.rank)
        for ind in this_voigt_map:
            v_matrix[this_voigt_map[ind]] = self[ind]
        if not self.is_voigt_symmetric():
            warnings.warn("Tensor is not symmetric, information may "
                          "be lost in voigt conversion.")
        return v_matrix * self._vscale