code: def deleteEdge(self, edge, waitForSync = False) :
          
          url = "%s/edge/%s" % (self.URL, edge._id)
          r = self.connection.session.delete(url, params = {'waitForSync' : waitForSync})
          if r.status_code == 200 or r.status_code == 202 :
              return True
          raise DeletionError("Unable to delete edge, %s" % edge._id, r.json())
docs: removes an edge from the graph