code: def test_descendants_at_distance(self):
      for distance, descendants in enumerate([{0}, {1}, {2, 3}, {4}]):
          assert (
              nx.descendants_at_distance(self.G, 0, distance)
              == descendants
          )
  
imports: from functools import partial
  import pytest
  import networkx
label_desc: Use image node_id 11 for calling the TestBFS obj's underlying member method code with example usage: obj.test_descendants_at_distance() without return types