message: Remove unused import in nn_impl.py
diff: @@ -24,7 +24,6 @@ from tensorflow.python.compat import compat
  from tensorflow.python.distribute import distribution_strategy_context as ds
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  -from tensorflow.python.framework import function
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import candidate_sampling_ops
  