code: def testSliceFilteringSelect(self):
      subset = self.g.vs.select(slice(5, 8))
      self.assertTrue(len(subset) == 3)
      self.assertTrue(subset["test"] == [5, 6, 7])
      subset = self.g.vs[5:16:2]
      self.assertTrue(len(subset) == 3)
      self.assertTrue(subset["test"] == [5, 7, 9])
  
imports: import unittest
  from igraph import Graph, Vertex, VertexSeq
  from .utils import is_pypy
label_desc: Use image node_id 16 for calling the VertexSeqTests obj's underlying member method code with example usage: obj.testSliceFilteringSelect() without return types