code: def testPartialAttributeAssignment(self):
      only_even = self.g.vs.select(lambda v: (v.index % 2 == 0))
      only_even["test"] = [0] * len(only_even)
      self.assertTrue(
          self.g.vs["test"] == [0, 1, 0, 3, 0, 5, 0, 7, 0, 9]
      )
      only_even["test2"] = list(range(5))
      self.assertTrue(
          self.g.vs["test2"]
          == [0, None, 1, None, 2, None, 3, None, 4, None]
      )
  
imports: import unittest
  from igraph import Graph, Vertex, VertexSeq
  from .utils import is_pypy
label_desc: Use image node_id 5 for calling the VertexSeqTests obj's underlying member method code with example usage: obj.testPartialAttributeAssignment() without return types