code: def setup_class(cls):
      from networkx import convert_node_labels_to_integers as cnlti
  
      cls.grid = cnlti(
          nx.grid_2d_graph(4, 4), first_label=1, ordering="sorted"
      )
      cls.cycle = nx.cycle_graph(7)
      cls.directed_cycle = nx.cycle_graph(7, create_using=nx.DiGraph())
      cls.neg_weights = nx.DiGraph()
      cls.neg_weights.add_edge(0, 1, weight=1)
      cls.neg_weights.add_edge(0, 2, weight=3)
      cls.neg_weights.add_edge(1, 3, weight=1)
      cls.neg_weights.add_edge(2, 3, weight=-2)
  
imports: import pytest
  import networkx
label_desc: Use image node_id 1 for calling the TestGenericPath obj's underlying member method code with example usage: obj.setup_class(cls) without return types