code: def testReingoldTilford(self):
      g = Graph.Barabasi(100)
      lo = g.layout("rt")
      ys = [coord[1] for coord in lo]
      root = ys.index(0.0)
      self.assertEqual(ys, g.distances(root)[0])
      g = Graph.Barabasi(100) + Graph.Barabasi(50)
      lo = g.layout("rt", root=[0, 100])
      self.assertEqual(lo[100][1] - lo[0][1], 0)
      lo = g.layout("rt", root=[0, 100], rootlevel=[2, 10])
      self.assertEqual(lo[100][1] - lo[0][1], 8)
  
      # test named vertices
      g.vs["name"] = [f"v{i}" for i in range(g.vcount())]
      lo = g.layout("rt", root=["v0", "v100"])
      self.assertEqual(lo[100][1] - lo[0][1], 0)
  
imports: import unittest
  from math import hypot
  from igraph import Graph, Layout, BoundingBox, InternalError
  from igraph import umap_compute_weights
label_desc: Use image node_id 11 for calling the LayoutAlgorithmTests obj's underlying member method code with example usage: obj.testReingoldTilford() without return types