code: def setup_class(cls):
      edges = [
          ("s", "u", 10),
          ("s", "x", 5),
          ("u", "v", 1),
          ("u", "x", 2),
          ("v", "y", 1),
          ("x", "u", 3),
          ("x", "v", 5),
          ("x", "y", 2),
          ("y", "s", 7),
          ("y", "v", 6),
      ]
      cls.XG = nx.DiGraph()
      cls.XG.add_weighted_edges_from(edges)
  
imports: import pytest
  import networkx
  from networkx.utils import pairwise
label_desc: Use image node_id 1 for calling the TestAStar obj's underlying member method code with example usage: obj.setup_class(cls) without return types