code: def test_degree_histogram(self):
      assert nx.degree_histogram(self.G) == [1, 1, 1, 1, 1]
  
imports: import random
  import pytest
  import networkx
  from networkx.utils import edges_equal, nodes_equal
label_desc: Use image node_id 15 for calling the TestFunction obj's underlying member method code with example usage: obj.test_degree_histogram() without return types