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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 _graph_add_edge(self, cfg_node, src_node, src_jumpkind, src_ins_addr, src_stmt_idx):
 """ Add edge between nodes, or add node if entry point :param CFGNode cfg_node: node which is jumped to :param CFGNode src_node: node which is jumped from none if entry point :param str src_jumpkind: what type of jump the edge takes :param int or str src_stmt_idx: source statements ID :return: None """


        if src_node is None:
            self.graph.add_node(cfg_node)
        else:
            self.graph.add_edge(src_node, cfg_node, jumpkind=src_jumpkind, ins_addr=src_ins_addr,
                                stmt_idx=src_stmt_idx)