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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 all_successors(self, node, skip_reached_fixedpoint=False):
 """ Returns all successors to the specific node. :param node: A node in the graph. :return: A set of nodes that are all successors to the given node. :rtype: set """


        successors = set()

        stack = [ node ]
        while stack:
            n = stack.pop()
            successors.add(n)
            stack.extend(succ for succ in self.successors(n) if
                         succ not in successors and
                            (not skip_reached_fixedpoint or succ not in self._reached_fixedpoint)
                         )

        return successors