Get all predecessors of a specific node on the control flow graph.

        :param CFGNode cfgnode: The CFGNode object
        :return: A list of predecessors in the CFG
        :rtype: list

def get_all_predecessors(self, cfgnode):
        """
        Get all predecessors of a specific node on the control flow graph.

        :param CFGNode cfgnode: The CFGNode object
        :return: A list of predecessors in the CFG
        :rtype: list
        """
        s = set()
        for child, parent in networkx.dfs_predecessors(self.graph, cfgnode).items():
            s.add(child)
            s.add(parent)
        return list(s)