code: def testIntersectionSingle(self):
      g1 = Graph.Tree(7, 2)
      g = intersection([g1])
      self.assertTrue(g != g1)
      self.assertTrue(
          g.vcount() == g1.vcount() and g.ecount() == g1.ecount()
      )
      self.assertTrue(g.is_directed() == g1.is_directed())
      self.assertTrue(g.get_edgelist() == g1.get_edgelist())
  
imports: import unittest
  from igraph import Graph, disjoint_union, intersection, union
label_desc: Use image node_id 19 for calling the OperatorTests obj's underlying member method code with example usage: obj.testIntersectionSingle() without return types