code: def test_invalid_block_size(self):
      x = testing.shaped_arange((2, 3, 4), cupy, cupy.float32)
      kernel = cupy.ElementwiseKernel("T x, T y", "T z", "z = x + y")
      with pytest.raises(ValueError):
          kernel(x, 1, block_size=0)
  
imports: import unittest
  import numpy
  import pytest
  import cupy
  from cupy import testing
  from cupy.cuda import runtime
  from cupy.cuda.texture import ChannelFormatDescriptor, CUDAarray, ResourceDescriptor, TextureDescriptor, TextureObject
label_desc: Use image node_id 1 for calling the TestUserkernelManualBlockSize obj's underlying member method code with example usage: obj.test_invalid_block_size() without return types