code: def test_astar_nopath(self):
      with pytest.raises(nx.NodeNotFound):
          nx.astar_path(self.XG, "s", "moon")
  
imports: import pytest
  import networkx
  from networkx.utils import pairwise
label_desc: Use image node_id 13 for calling the TestAStar obj's underlying member method code with example usage: obj.test_astar_nopath() without return types