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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 mrs(self):
 """ Deserialize and return an Mrs object for simplemrs or JSON-formatted MRS data; otherwise return the original string. """

        mrs = self.get('mrs')
        if mrs is not None:
            if isinstance(mrs, dict):
                mrs = Mrs.from_dict(mrs)
            elif isinstance(mrs, stringtypes):
                mrs = simplemrs.loads_one(mrs)
        return mrs