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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 register_subservice(self, uri, service):
 """Register a class instance to handle a URI. :param uri: string - URI for the request :param service: StackInABoxService object instance that handles the request :returns: n/a """

        found = False

        self.create_route(uri, True)
        self.routes[uri]['handlers'].set_subservice(service)