code: def test_add_nodes_from_non_string(self):
      self.graph = DAG()
      self.graph.add_nodes_from([1, 2, 3, 4])
  
      self.graph = DAG()
      self.graph.add_nodes_from([1, 2, 3, 4], latent=True)
  
      self.graph = DAG()
      self.graph.add_nodes_from(
          [1, 2, 3, 4], latent=[True, False, False, False]
      )
  
imports: import unittest
  import networkx
  import numpy
  import pgmpy.tests.help_functions
  from pgmpy.base import DAG, PDAG
label_desc: Use image node_id 7 for calling the TestDAGCreation obj's underlying member method code with example usage: obj.test_add_nodes_from_non_string() without return types