code: def test_greedy_modularity_communities_corner_cases():
      G = nx.empty_graph()
      assert nx.community.greedy_modularity_communities(G) == []
      G.add_nodes_from(range(3))
      assert nx.community.greedy_modularity_communities(G) == [
          {0},
          {1},
          {2},
      ]
  
file_path: networkx/networkx/algorithms/community/tests/test_modularity_max.py
imports: import pytest
  import networkx
  from networkx.algorithms.community import greedy_modularity_communities, naive_greedy_modularity_communities
label_desc: Use image node_id 16 for calling a global function with example usage: test_greedy_modularity_communities_corner_cases() without return types