code: def test_every_two_item_no_storage(self):
      dtype = np.dtype(
          [
              ("position", np.float32, 3),
              ("texcoord", np.float32, 2),
              ("color", np.float32, 4),
          ]
      )
      data = np.zeros(10, dtype=dtype)
      B = DataBuffer(data)
      # with self.assertRaises(ValueError):
      #    B[::2] = data[::2]
      s = slice(None, None, 2)
      self.assertRaises(ValueError, B.__setitem__, s, data[::2])
  
imports: import unittest
  import numpy
  from vispy.testing import run_tests_if_main
  from vispy.gloo.buffer import Buffer, DataBuffer, DataBufferView, VertexBuffer, IndexBuffer
label_desc: Use image node_id 17 for calling the DataBufferTest obj's underlying member method code with example usage: obj.test_every_two_item_no_storage() without return types