code: def test_is_eulerian2(self):
      # not connected
      G = nx.Graph()
      G.add_nodes_from([1, 2, 3])
      assert not nx.is_eulerian(G)
      # not strongly connected
      G = nx.DiGraph()
      G.add_nodes_from([1, 2, 3])
      assert not nx.is_eulerian(G)
      G = nx.MultiDiGraph()
      G.add_edge(1, 2)
      G.add_edge(2, 3)
      G.add_edge(2, 3)
      G.add_edge(3, 1)
      assert not nx.is_eulerian(G)
  
imports: import collections
  import pytest
  import networkx
label_desc: Use image node_id 2 for calling the TestIsEulerian obj's underlying member method code with example usage: obj.test_is_eulerian2() without return types