code: def test_default_init(self):
      # Check default storage and copy flags
      data = np.ones(100)
      B = DataBuffer(data)
      assert B.nbytes == data.nbytes
      assert B.offset == 0
      assert B.size == 100
      assert B.itemsize == data.itemsize
      assert B.stride == data.itemsize
      assert B.dtype == data.dtype
  
      # Given data must be actual numeric data
      self.assertRaises(TypeError, DataBuffer, "this is not nice data")
  
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 1 for calling the DataBufferTest obj's underlying member method code with example usage: obj.test_default_init() without return types