code: def setup_class(cls):
      cls.nodes = [0, 1, 2, 3]
      cls.edges = [(0, 1), (1, 0), (1, 0), (2, 1), (3, 1)]
  
imports: import pytest
  import networkx
  from networkx.algorithms import edge_dfs
  from networkx.algorithms.traversal.edgedfs import FORWARD, REVERSE
label_desc: Use image node_id 1 for calling the TestEdgeDFS obj's underlying member method code with example usage: obj.setup_class(cls) without return types