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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 add_subdispatch(self, dispatcher, prefix=''):
 """Adds a subdispatcher, possibly in its own namespace. :param dispatcher: The dispatcher to add as a subdispatcher. :type dispatcher: RPCDispatcher :param str prefix: A prefix. All of the new subdispatchers methods will be available as prefix + their original name. """

        self.subdispatchers.setdefault(prefix, []).append(dispatcher)