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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_handler(self, callable_obj, entrypoint, methods=('GET',)):
 """Register a handler callable to a specific route. Args: entrypoint (str):
 The uri relative path. methods (tuple):
 A tuple of valid method strings. callable_obj (callable):
 The callable object. Returns: The Router instance (for chaining purposes). Raises: RouteError, for missing routing params or invalid callable object type. """


        router_obj = Route.wrap_callable(
            uri=entrypoint,
            methods=methods,
            callable_obj=callable_obj
        )

        if router_obj.is_valid:
            self._routes.add(router_obj)
            return self
        
        raise RouteError(  # pragma: no cover
            "Missing params: methods: {} - entrypoint: {}".format(
                methods, entrypoint
            )
        )