code: def testShiftOperation(self):
      shift_operation = mtf.ShiftOperation(
          self.x, -5, self.b_dim, wrap=True
      )
      self.assertEqual(
          shift_operation.splittable_dims, frozenset(["a", "b"])
      )
      self.assertEqual(shift_operation.unsplittable_dims, frozenset())
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  import mesh_tensorflow
  from mesh_tensorflow import test_utils
  import numpy
  import tensorflow.compat.v1
  from tensorflow.python.framework import test_util
label_desc: Use image node_id 15 for calling the OperationSplittabilityTest obj's underlying member method code with example usage: obj.testShiftOperation() without return types