langchain/graphs/networkx_graph.py/NetworkxEntityGraph/get_entity_knowledge
class NetworkxEntityGraph:    def get_entity_knowledge(self, entity: str, depth: int = 1) -> List[str]:
        """Get information about an entity."""
        import networkx as nx

        # TODO: Have more information-specific retrieval methods
        if not self._graph.has_node(entity):
            return []

        results = []
        for src, sink in nx.dfs_edges(self._graph, entity, depth_limit=depth):
            relation = self._graph[src][sink]["relation"]
            results.append(f"{src} {relation} {sink}")
        return results