arangosh> var examples = require("@arangodb/graph-examples/example-graph.js");
arangosh> var graph = examples.loadGraph("social");
arangosh> graph.relation.save(
........>  "relation/aliceAndBob",
........>   "female/alice",
........> {type: "married", _key: "bobAndAlice"});
[ArangoError 1906: invalid edge between relation/aliceAndBob and female/alice. Doesn't conform to any edge definition]