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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 method(*args, **kwargs):
 """Annotate an actor method. .. code-block:: python @ray.remote class Foo(object):
 @ray.method(num_return_vals=2) def bar(self):
 return 1, 2 f = Foo.remote() _, _ = f.bar.remote() Args: num_return_vals: The number of object IDs that should be returned by invocations of this actor method. """

    assert len(args) == 0
    assert len(kwargs) == 1
    assert "num_return_vals" in kwargs
    num_return_vals = kwargs["num_return_vals"]

    def annotate_method(method):
        method.__ray_num_return_vals__ = num_return_vals
        return method

    return annotate_method