code: def test_k_is_7():
      G = nx.Graph(
          [
              (1, 11),
              (1, 12),
              (1, 13),
              (1, 14),
              (1, 15),
              (1, 16),
              (1, 17),
              (1, 18),
              (2, 11),
              (2, 12),
              (2, 13),
              (2, 14),
              (2, 15),
              (2, 16),
              (2, 17),
              (2, 19),
              (3, 11),
              (3, 12),
              (3, 13),
              (3, 14),
              (3, 15),
              (3, 16),
              (3, 17),
              (3, 20),
              (4, 11),
              (4, 12),
              (4, 13),
              (4, 14),
              (4, 15),
              (4, 16),
              (4, 17),
              (4, 18),
              (4, 19),
              (4, 20),
              (5, 11),
              (5, 12),
              (5, 13),
              (5, 14),
              (5, 15),
              (5, 16),
              (5, 17),
              (5, 18),
              (5, 19),
              (5, 20),
              (6, 11),
              (6, 12),
              (6, 13),
              (6, 14),
              (6, 15),
              (6, 16),
              (6, 17),
              (6, 18),
              (6, 19),
              (6, 20),
              (7, 11),
              (7, 12),
              (7, 13),
              (7, 14),
              (7, 15),
              (7, 16),
              (7, 17),
              (7, 18),
              (7, 19),
              (7, 20),
              (8, 11),
              (8, 12),
              (8, 13),
              (8, 14),
              (8, 15),
              (8, 16),
              (8, 17),
              (8, 18),
              (8, 19),
              (8, 20),
              (9, 11),
              (9, 12),
              (9, 13),
              (9, 14),
              (9, 15),
              (9, 16),
              (9, 17),
              (9, 18),
              (9, 19),
              (9, 20),
              (10, 11),
              (10, 12),
              (10, 13),
              (10, 14),
              (10, 15),
              (10, 16),
              (10, 17),
              (10, 18),
              (10, 19),
              (10, 20),
          ]
      )
      assert nx.bipartite.maximal_extendability(G) == 7
  
file_path: networkx/networkx/algorithms/bipartite/tests/test_extendability.py
imports: import pytest
  import networkx
label_desc: Use image node_id 11 for calling a global function with example usage: test_k_is_7() without return types