code: def test_structured_init(self):
      # Check structured type
      dtype = np.dtype(
          [
              ("position", np.float32, 3),
              ("texcoord", np.float32, 2),
              ("color", np.float32, 4),
          ]
      )
      data = np.zeros(10, dtype=dtype)
      B = DataBuffer(data)
      assert B.nbytes == data.nbytes
      assert B.offset == 0
      assert B.size == 10
      assert B.itemsize == data.itemsize
      assert B.stride == data.itemsize
      assert B.dtype == data.dtype
  
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 2 for calling the DataBufferTest obj's underlying member method code with example usage: obj.test_structured_init() without return types