code: def test_set_keys_invalid_index(self):
      with self.assertRaises(IndexError):
          self.dataset.keys = 4
  
imports: import numpy
  import unittest
  from chainercv.chainer_experimental.datasets.sliceable import GetterDataset
  from chainercv.utils import testing
label_desc: Use image node_id 13 for calling the TestGetterDataset obj's underlying member method code with example usage: obj.test_set_keys_invalid_index() without return types