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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_input_state(self, node, input_state):
 """ Add the input state to all successors of the given node. :param node: The node whose successors' input states will be touched. :param input_state: The state that will be added to successors of the node. :return: None """


        successors = self._graph_visitor.successors(node)

        for succ in successors:
            if succ in self._state_map:
                self._state_map[succ] = self._merge_states(succ, *([ self._state_map[succ], input_state ]))
            else:
                self._state_map[succ] = input_state