code: def test_stack_value(self):
      a = testing.shaped_arange((2, 3), cupy)
      b = testing.shaped_arange((2, 3), cupy)
      c = testing.shaped_arange((2, 3), cupy)
      s = cupy.stack((a, b, c))
      assert s.shape == (3, 2, 3)
      cupy.testing.assert_array_equal(s[0], a)
      cupy.testing.assert_array_equal(s[1], b)
      cupy.testing.assert_array_equal(s[2], c)
  
imports: import numpy
  import pytest
  import cupy
  from cupy import testing
  from cupy import cuda
label_desc: Use image node_id 44 for calling the TestJoin obj's underlying member method code with example usage: obj.test_stack_value() without return types