langchain/graphs/networkx_graph.py/NetworkxEntityGraph/delete_triple
class NetworkxEntityGraph:    def delete_triple(self, knowledge_triple: KnowledgeTriple) -> None:
        """Delete a triple from the graph."""
        if self._graph.has_edge(knowledge_triple.subject, knowledge_triple.object_):
            self._graph.remove_edge(knowledge_triple.subject, knowledge_triple.object_)