code: def test_input_validation(self):
      devices = [f"cpu:{i}" for i in range(4)]
      with self.assertRaisesRegex(
          ValueError, "Shape and axis_names cannot be empty"
      ):
          distribution_lib.DeviceMesh((4,), "", devices)
  
      with self.assertRaisesRegex(
          ValueError, "Shape and axis_names should have same size"
      ):
          distribution_lib.DeviceMesh((4, 2), ["batch"], devices)
  
      with self.assertRaisesRegex(
          ValueError, "Shape does not match the number of devices"
      ):
          distribution_lib.DeviceMesh(
              (4, 2), ["batch", "model"], devices
          )
  
imports: import os
  from unittest import mock
  import numpy
  import pytest
  import tensorflow
  from keras import backend
  from keras import testing
  from keras.backend import distribution_lib
  from keras.distribution import distribution_lib
label_desc: Use image node_id 2 for calling the DeviceMeshTest obj's underlying member method code with example usage: obj.test_input_validation() without return types