code: def testCombinationFirst(self):
      g = self.g
      g.es["weight2"] = [1, 0, 2, 6, 8, 4, 7]
      g.simplify(combine_edges="first")
      self.assertTrue(g.es["weight"] == [1, 3, 4])
      self.assertTrue(g.es["weight2"] == [1, 2, 6])
  
imports: import unittest
  from igraph import Graph
label_desc: Use image node_id 9 for calling the AttributeCombinationTests obj's underlying member method code with example usage: obj.testCombinationFirst() without return types