code: def test_alpha(self, im_shape, input_type):
      im = self.get_data(im_shape, input_type)
      alpha = [0.5, 0.51]
      t = RandGibbsNoise(1.0, alpha)
      _ = t(deepcopy(im))
      self.assertGreaterEqual(t.sampled_alpha, 0.5)
      self.assertLessEqual(t.sampled_alpha, 0.51)
  
file_path: MONAI/tests/test_rand_gibbs_noise.py
imports: from __future__ import annotations
  import unittest
  from copy import deepcopy
  import numpy
  from parameterized import parameterized
  from monai.data.synthetic import create_test_image_2d, create_test_image_3d
  from monai.transforms import RandGibbsNoise
  from monai.utils.misc import set_determinism
  from monai.utils.module import optional_import
  from tests.utils import TEST_NDARRAYS, assert_allclose
label_desc: Use image node_id 8 for calling the TestRandGibbsNoise obj's underlying member method code with example usage: obj.test_alpha(im_shape, input_type) without return types