code: def __call__(self, x):
      return x * 2
  
file_path: MONAI/tests/test_randidentity.py
imports: from __future__ import annotations
  import unittest
  import monai.transforms
  from monai.data import CacheDataset
  from tests.utils import TEST_NDARRAYS, NumpyImageTestCase2D, assert_allclose
label_desc: Use image node_id 1 for calling the T obj's underlying member method code with example usage: obj.__call__(x) and returns: unknown