message: use self.assertRaises
diff: @@ -20,8 +20,6 @@ from __future__ import print_function
  import numpy as np
  -import pytest
  -
  from tensorflow.python.compat import compat
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes as dtypes_lib
  @@ -1233,8 +1231,7 @@ class PolyvalTest(test.TestCase):
  def test_coeffs_raise(self):
  x = np.random.rand(2, 2).astype(np.float32)
  coeffs = {}
  - msg = "Argument coeffs must be list type."
  - with pytest.raises(ValueError, match=msg):
  + with self.assertRaises(ValueError):
  math_ops.polyval(coeffs, x)
  