Get a named actor which was previously created.

    If the actor doesn't exist, an exception will be raised.

    Args:
        name: The name of the named actor.

    Returns:
        The ActorHandle object corresponding to the name.

def get_actor(name):
    """Get a named actor which was previously created.

    If the actor doesn't exist, an exception will be raised.

    Args:
        name: The name of the named actor.

    Returns:
        The ActorHandle object corresponding to the name.
    """
    actor_name = _calculate_key(name)
    pickled_state = _internal_kv_get(actor_name)
    if pickled_state is None:
        raise ValueError("The actor with name={} doesn't exist".format(name))
    handle = pickle.loads(pickled_state)
    return handle