code: def test_zero_prob(self):
      bias_field = RandBiasField(prob=0.0)
      img = np.random.rand(3, 32, 32)
      output = bias_field(img)
      np.testing.assert_equal(output, img)
  
file_path: MONAI/tests/test_rand_bias_field.py
imports: from __future__ import annotations
  import unittest
  import numpy
  import torch
  from parameterized import parameterized
  from monai.transforms import RandBiasField
  from tests.utils import TEST_NDARRAYS
label_desc: Use image node_id 4 for calling the TestRandBiasField obj's underlying member method code with example usage: obj.test_zero_prob() without return types