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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 get_rms_dist(self, struct1, struct2):
 """ Calculate RMS displacement between two structures Args: struct1 (Structure):
 1st structure struct2 (Structure):
 2nd structure Returns: rms displacement normalized by (Vol / nsites) ** (1/3) and maximum distance between paired sites. If no matching lattice is found None is returned. """

        struct1, struct2 = self._process_species([struct1, struct2])
        struct1, struct2, fu, s1_supercell = self._preprocess(struct1, struct2)
        match = self._match(struct1, struct2, fu, s1_supercell, use_rms=True,
                            break_on_match=False)

        if match is None:
            return None
        else:
            return match[0], max(match[1])