class_docstr: Unit tests for the multi-source dialect of Dijkstra's shortest
  path algorithms.
class_docstr_tok: ["Unit","tests","for","the","multi-source","dialect","of","Dijkstra","'s","shortest","path","algorithms","."]
code: def test_absent_source(self, fn):
      G = nx.path_graph(2)
      with pytest.raises(nx.NodeNotFound):
          fn(G, [3], 0)
      with pytest.raises(nx.NodeNotFound):
          fn(G, [3], 3)
  
imports: import pytest
  import networkx
  from networkx.utils import pairwise
label_desc: Use image node_id 4 for calling the TestMultiSourceDijkstra obj's underlying member method code with example usage: obj.test_absent_source(fn) without return types