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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 morphs(self, name, index_name=None):
 """ Add the proper columns for a polymorphic table. :type name: str :type index_name: str """

        self.unsigned_integer("%s_id" % name)
        self.string("%s_type" % name)
        self.index(["%s_id" % name, "%s_type" % name], index_name)