code: def test_is_connected(self):
      assert nx.is_connected(self.grid)
      G = nx.Graph()
      G.add_nodes_from([1, 2])
      assert not nx.is_connected(G)
  
file_path: networkx/networkx/algorithms/components/tests/test_connected.py
imports: import pytest
  import networkx
  from networkx import NetworkXNotImplemented
  from networkx import convert_node_labels_to_integers
  from networkx.classes.tests import dispatch_interface
label_desc: Use image node_id 7 for calling the TestConnected obj's underlying member method code with example usage: obj.test_is_connected() without return types