message: Removed references to _ref types in documentation.
  See
diff: @@ -57,9 +57,6 @@ class DType(object):
  * `tf.resource`: Handle to a mutable resource.
  * `tf.variant`: Values of arbitrary types.
  - In addition, variants of these types with the `_ref` suffix are
  - defined for reference-typed tensors.
  -
  The `tf.as_dtype()` function converts numpy types and string type
  names to a `DType` object.
  """
  @@ -247,9 +244,6 @@ class DType(object):
  ```python
  DType(T) .is_compatible_with(DType(T)) == True
  - DType(T) .is_compatible_with(DType(T).as_ref) == True
  - DType(T).as_ref.is_compatible_with(DType(T)) == False
  - DType(T).as_ref.is_compatible_with(DType(T).as_ref) == True
  ```
  Args:
  