code: def setup_class(cls):
      # simple graph
      G = nx.Graph()
      G.add_edges_from([(0, 1), (1, 2), (1, 3), (2, 4), (3, 4)])
      cls.G = G
  
imports: from functools import partial
  import pytest
  import networkx
label_desc: Use image node_id 1 for calling the TestBFS obj's underlying member method code with example usage: obj.setup_class(cls) without return types