The only type of edge atm that is valid is `(a)-[e1]->(b)` and I would like to add support for `(a)-[e1]-(b)` in [GraphFrame.find()](https://graphframes.github.io/graphframes/docs/_site/api/python/graphframes.html#graphframes.GraphFrame.find).