code: def test_tree_all_pairs_lca_generator(self):
      pairs = iter([(0, 1), (0, 1), (1, 0)])
      some_pairs = dict(tree_all_pairs_lca(self.DG, 0, pairs))
      assert (0, 1) in some_pairs and (1, 0) in some_pairs
      assert len(some_pairs) == 2
  
imports: from itertools import chain, combinations, product
  import pytest
  import networkx
label_desc: Use image node_id 11 for calling the TestTreeLCA obj's underlying member method code with example usage: obj.test_tree_all_pairs_lca_generator() without return types