code: def test_k_corona(self):
      # k=0
      k_corona_subgraph = nx.k_corona(self.H, k=2)
      assert sorted(k_corona_subgraph.nodes()) == [2, 4, 5, 6]
      # k=1
      k_corona_subgraph = nx.k_corona(self.H, k=1)
      assert sorted(k_corona_subgraph.nodes()) == [1]
      # k=2
      k_corona_subgraph = nx.k_corona(self.H, k=0)
      assert sorted(k_corona_subgraph.nodes()) == [0]
  
imports: import pytest
  import networkx
  from networkx.utils import nodes_equal
label_desc: Use image node_id 17 for calling the TestCore obj's underlying member method code with example usage: obj.test_k_corona() without return types