message: adding test for heterogeneous dataset from generator
diff: @@ -503,6 +503,24 @@ class DatasetConstructorTest(test.TestCase):
  with self.assertRaises(errors.OutOfRangeError):
  sess.run(get_next)
  + def testFromGeneratorHeterogeneous(self):
  + def generator():
  + yield 1
  + yield [2, 3]
  +
  + iterator = (
  + dataset_ops.Dataset.from_generator(
  + generator, output_types=dtypes.int64).make_initializable_iterator())
  + init_op = iterator.initializer
  + get_next = iterator.get_next()
  +
  + with self.test_session() as sess:
  + sess.run(init_op)
  + self.assertAllEqual(1, sess.run(get_next))
  + self.assertAllEqual([2, 3], sess.run(get_next))
  + with self.assertRaises(errors.OutOfRangeError):
  + sess.run(get_next)
  +
  def testSplitPipelineFailsWithPlacementError(self):
  with session.Session(
  target="",
  