code: def test_path_projected_graph(self):
      G = nx.path_graph(4)
      P = bipartite.projected_graph(G, [1, 3])
      assert nodes_equal(list(P), [1, 3])
      assert edges_equal(list(P.edges()), [(1, 3)])
      P = bipartite.projected_graph(G, [0, 2])
      assert nodes_equal(list(P), [0, 2])
      assert edges_equal(list(P.edges()), [(0, 2)])
      G = nx.MultiGraph([(0, 1)])
      with pytest.raises(
          nx.NetworkXError, match="not defined for multigraphs"
      ):
          bipartite.projected_graph(G, [0])
  
imports: import pytest
  import networkx
  from networkx.algorithms import bipartite
  from networkx.utils import edges_equal, nodes_equal
label_desc: Use image node_id 1 for calling the TestBipartiteProject obj's underlying member method code with example usage: obj.test_path_projected_graph() without return types