code: def testContractVerticesWithNumPyIntegers(self):
      g = Graph.Full(4) + Graph.Full(4) + [(0, 5), (1, 4)]
      g2 = g.copy()
      g2.contract_vertices(
          [np.int32(x) for x in [0, 1, 2, 3, 1, 0, 6, 7]]
      )
      self.assertEqual(g2.vcount(), 8)
      self.assertEqual(g2.ecount(), g.ecount())
      self.assertEqual(
          sorted(g2.get_edgelist()),
          [
              (0, 0),
              (0, 1),
              (0, 1),
              (0, 2),
              (0, 3),
              (0, 6),
              (0, 7),
              (1, 1),
              (1, 2),
              (1, 3),
              (1, 6),
              (1, 7),
              (2, 3),
              (6, 7),
          ],
      )
  
imports: import unittest
  from igraph import Graph, disjoint_union, intersection, union
label_desc: Use image node_id 30 for calling the OperatorTests obj's underlying member method code with example usage: obj.testContractVerticesWithNumPyIntegers() without return types