message: Convert bytes to string.
diff: @@ -334,7 +334,7 @@ class TPUReplicateContext(control_flow_ops.XLAControlFlowContext):
  self._gradient_colocation_stack.append(op)
  if not self._outside_compilation_cluster:
  try:
  - outside_attr = op.get_attr(_OUTSIDE_COMPILATION_ATTR)
  + outside_attr = op.get_attr(_OUTSIDE_COMPILATION_ATTR).decode("ascii")
  if self._in_gradient_colocation:
  raise NotImplementedError(
  "Cannot nest gradient colocation operations outside compilation"
  