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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 _populate_route_attributes(self):
 """ Converts all routes from forward references to complete definitions. """

        route_schema = self._validate_stone_cfg()
        self.api.add_route_schema(route_schema)
        for namespace in self.api.namespaces.values():
            env = self._get_or_create_env(namespace.name)
            for route in namespace.routes:
                self._populate_route_attributes_helper(env, route, route_schema)