Add a colab for generating figures.

Export training curves to file and fix some inconsistencies.

PiperOrigin-RevId: 324825810

option_keyboard/environment_wrappers.py

@@ -135,7 +135,7 @@ class EnvironmentWithKeyboard(dm_env.Environment):
         break
 
       # Terminate option.
-      if self._compute_reward(option, action_step.observation) > 0:
+      if self._should_terminate(option, action_step.observation):
         break
 
       if not self._call_and_return:
@@ -143,6 +143,16 @@ class EnvironmentWithKeyboard(dm_env.Environment):
 
     return option_step
 
+  def _should_terminate(self, option, obs):
+    if self._compute_reward(option, obs) > 0:
+      return True
+    elif np.all(self._options_np[option] <= 0):
+      # TODO(shaobohou) A hack ensure option with non-positive weights
+      # terminates after one step
+      return True
+    else:
+      return False
+
   def action_spec(self):
     return dm_env.specs.DiscreteArray(
         num_values=self._options_np.shape[0], name="action")
@@ -228,7 +238,7 @@ class EnvironmentWithKeyboardDirect(dm_env.Environment):
         break
 
       # Terminate option.
-      if self._compute_reward(option, action_step.observation) > 0:
+      if self._should_terminate(option, action_step.observation):
         break
 
       if not self._call_and_return:
@@ -236,6 +246,16 @@ class EnvironmentWithKeyboardDirect(dm_env.Environment):
 
     return option_step
 
+  def _should_terminate(self, option, obs):
+    if self._compute_reward(option, obs) > 0:
+      return True
+    elif np.all(option <= 0):
+      # TODO(shaobohou) A hack ensure option with non-positive weights
+      # terminates after one step
+      return True
+    else:
+      return False
+
   def action_spec(self):
     return dm_env.specs.BoundedArray(shape=(self._keyboard.num_cumulants,),
                                      dtype=np.float32,
@@ -280,10 +300,7 @@ def _discretize_actions(num_actions_per_dim,
 
   # Remove options with all zeros.
   non_zero_entries = np.sum(np.square(discretized_actions), axis=-1) != 0.0
-  # Remove options with no positive elements.
+  discretized_actions = discretized_actions[non_zero_entries]
-  non_negative_entries = np.any(discretized_actions > 0, axis=-1)
-  discretized_actions = discretized_actions[np.logical_and(
-      non_zero_entries, non_negative_entries)]
   logging.info("Total number of discretized actions: %s",
                len(discretized_actions))
   logging.info("Discretized actions: %s", discretized_actions)

option_keyboard/experiment.py

@@ -16,7 +16,10 @@
 # ============================================================================
 """A simple training loop."""
 
+import csv
+
 from absl import logging
+from tensorflow.compat.v1.io import gfile
 
 
 def _ema(base, val, decay=0.995):
@@ -32,31 +35,42 @@ def run(env, agent, num_episodes, report_every=200, num_eval_reps=1):
     num_episodes: Number of episodes to train for.
     report_every: Frequency at which training progress are reported (episodes).
     num_eval_reps: Number of eval episodes to run per training episode.
+
+  Returns:
+    A list of dicts containing training and evaluation returns, and a list of
+    reported returns smoothed by EMA.
   """
 
-  train_returns = []
+  returns = []
+  logged_returns = []
   train_return_ema = 0.
-  eval_returns = []
   eval_return_ema = 0.
-  for episode_id in range(num_episodes):
+  for episode in range(num_episodes):
+    returns.append(dict(episode=episode))
+
     # Run a training episode.
     train_episode_return = run_episode(env, agent, is_training=True)
-    train_returns.append(train_episode_return)
     train_return_ema = _ema(train_return_ema, train_episode_return)
+    returns[-1]["train"] = train_episode_return
 
     # Run an evaluation episode.
+    returns[-1]["eval"] = []
     for _ in range(num_eval_reps):
       eval_episode_return = run_episode(env, agent, is_training=False)
-      eval_returns.append(eval_episode_return)
       eval_return_ema = _ema(eval_return_ema, eval_episode_return)
+      returns[-1]["eval"].append(eval_episode_return)
 
-    if ((episode_id + 1) % report_every) == 0:
+    if ((episode + 1) % report_every) == 0 or episode == 0:
+      logged_returns.append(
+          dict(episode=episode, train=train_return_ema, eval=[eval_return_ema]))
       logging.info("Episode %s, avg train return %.3f, avg eval return %.3f",
-                   episode_id + 1, train_return_ema, eval_return_ema)
+                   episode + 1, train_return_ema, eval_return_ema)
       if hasattr(agent, "get_logs"):
-        logging.info("Episode %s, agent logs: %s", episode_id + 1,
+        logging.info("Episode %s, agent logs: %s", episode + 1,
                      agent.get_logs())
 
+  return returns, logged_returns
+
 
 def run_episode(environment, agent, is_training=False):
   """Run a single episode."""
@@ -75,3 +89,14 @@ def run_episode(environment, agent, is_training=False):
   episode_return = environment.episode_return
 
   return episode_return
+
+
+def write_returns_to_file(path, returns):
+  """Write returns to file."""
+
+  with gfile.GFile(path, "w") as file:
+    writer = csv.writer(file, delimiter=" ", quoting=csv.QUOTE_MINIMAL)
+    writer.writerow(["episode", "train"] +
+                    [f"eval_{idx}" for idx in range(len(returns[0]["eval"]))])
+    for row in returns:
+      writer.writerow([row["episode"], row["train"]] + row["eval"])

option_keyboard/gpe_gpi_experiments/eval_keyboard_fig5.py

@@ -30,7 +30,7 @@ python3 train_keyboard.py --logtostderr --policy_weights_name=5
 
 Then generate the polar plot data as follows:
 
-python3 eval_keyboard_fig5a.py --logtostderr \
+python3 eval_keyboard_fig5.py --logtostderr \
   --keyboard_paths=/tmp/option_keyboard/keyboard_12/tfhub,/tmp/option_keyboard/keyboard_34/tfhub,/tmp/option_keyboard/keyboard_5/tfhub \
   --num_episodes=1000
 
@@ -57,11 +57,14 @@ Example outout:
  [ 0.099       0.349       0.055     ]]
 """
 
+import csv
+
 from absl import app
 from absl import flags
 
 import numpy as np
 import tensorflow.compat.v1 as tf
+from tensorflow.compat.v1.io import gfile
 import tensorflow_hub as hub
 
 from option_keyboard import configs
@@ -75,20 +78,12 @@ from option_keyboard.gpe_gpi_experiments import regressed_agent
 FLAGS = flags.FLAGS
 flags.DEFINE_integer("num_episodes", 1000, "Number of training episodes.")
 flags.DEFINE_list("keyboard_paths", [], "Path to keyboard model.")
+flags.DEFINE_string("output_path", None, "Path to write out returns.")
 
 
-def evaluate_keyboard(keyboard_path):
+def evaluate_keyboard(keyboard_path, weights_to_sweep):
   """Evaluate a keyboard."""
 
-  angles_to_sweep = np.deg2rad(np.linspace(-90, 180, num=19, endpoint=True))
-  weights_to_sweep = np.stack(
-      [np.cos(angles_to_sweep),
-       np.sin(angles_to_sweep)], axis=-1)
-  weights_to_sweep /= np.sum(
-      np.maximum(weights_to_sweep, 0.0), axis=-1, keepdims=True)
-  weights_to_sweep = np.clip(weights_to_sweep, -1000, 1000)
-  tf.logging.info(weights_to_sweep)
-
   # Load the keyboard.
   keyboard = smart_module.SmartModuleImport(hub.Module(keyboard_path))
 
@@ -124,20 +119,41 @@ def evaluate_keyboard(keyboard_path):
                     f"{FLAGS.num_episodes} episodes is {np.mean(returns)}")
     all_returns.append(returns)
 
-  return all_returns, weights_to_sweep
+  return all_returns
 
 
 def main(argv):
   del argv
 
+  angles_to_sweep = np.deg2rad(np.linspace(-90, 180, num=19, endpoint=True))
+  weights_to_sweep = np.stack(
+      [np.sin(angles_to_sweep),
+       np.cos(angles_to_sweep)], axis=-1)
+  weights_to_sweep /= np.sum(
+      np.maximum(weights_to_sweep, 0.0), axis=-1, keepdims=True)
+  weights_to_sweep = np.clip(weights_to_sweep, -1000, 1000)
+  tf.logging.info(weights_to_sweep)
+
   all_returns = []
   for keyboard_path in FLAGS.keyboard_paths:
-    returns, _ = evaluate_keyboard(keyboard_path)
+    returns = evaluate_keyboard(keyboard_path, weights_to_sweep)
     all_returns.append(returns)
 
   print("Results:")
   print(np.mean(all_returns, axis=-1).T)
 
+  if FLAGS.output_path:
+    with gfile.GFile(FLAGS.output_path, "w") as file:
+      writer = csv.writer(file, delimiter=" ", quoting=csv.QUOTE_MINIMAL)
+      writer.writerow(["angle", "return", "idx"])
+      for idx, returns in enumerate(all_returns):
+        for row in np.array(returns).T.tolist():
+          assert len(angles_to_sweep) == len(row)
+          for ang, val in zip(angles_to_sweep, row):
+            ang = "{:.4g}".format(ang)
+            val = "{:.4g}".format(val)
+            writer.writerow([ang, val, idx])
+
 
 if __name__ == "__main__":
   tf.disable_v2_behavior()

option_keyboard/gpe_gpi_experiments/run_dqn_fig4b.py

@@ -32,6 +32,9 @@ from option_keyboard import scavenger
 
 FLAGS = flags.FLAGS
 flags.DEFINE_integer("num_episodes", 10000, "Number of training episodes.")
+flags.DEFINE_integer("report_every", 5,
+                     "Frequency at which metrics are reported.")
+flags.DEFINE_string("output_path", None, "Path to write out training curves.")
 
 
 def main(argv):
@@ -56,7 +59,13 @@ def main(argv):
       optimizer_name="AdamOptimizer",
       optimizer_kwargs=dict(learning_rate=3e-4,))
 
-  experiment.run(env, agent, num_episodes=FLAGS.num_episodes)
+  _, ema_returns = experiment.run(
+      env,
+      agent,
+      num_episodes=FLAGS.num_episodes,
+      report_every=FLAGS.report_every)
+  if FLAGS.output_path:
+    experiment.write_returns_to_file(FLAGS.output_path, ema_returns)
 
 
 if __name__ == "__main__":

option_keyboard/gpe_gpi_experiments/run_dqn_fig5.py

@@ -32,7 +32,10 @@ from option_keyboard import scavenger
 
 FLAGS = flags.FLAGS
 flags.DEFINE_integer("num_episodes", 10000, "Number of training episodes.")
-flags.DEFINE_list("test_w", [], "The w to test.")
+flags.DEFINE_list("test_w", None, "The w to test.")
+flags.DEFINE_integer("report_every", 200,
+                     "Frequency at which metrics are reported.")
+flags.DEFINE_string("output_path", None, "Path to write out training curves.")
 
 
 def main(argv):
@@ -58,7 +61,13 @@ def main(argv):
       optimizer_name="AdamOptimizer",
       optimizer_kwargs=dict(learning_rate=3e-4,))
 
-  experiment.run(env, agent, num_episodes=FLAGS.num_episodes)
+  _, ema_returns = experiment.run(
+      env,
+      agent,
+      num_episodes=FLAGS.num_episodes,
+      report_every=FLAGS.report_every)
+  if FLAGS.output_path:
+    experiment.write_returns_to_file(FLAGS.output_path, ema_returns)
 
 
 if __name__ == "__main__":

option_keyboard/gpe_gpi_experiments/run_regressed_w_fig4b.py

@@ -0,0 +1,97 @@
+# Lint as: python3
+# pylint: disable=g-bad-file-header
+# Copyright 2020 DeepMind Technologies Limited. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or  implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============================================================================
+r"""Run an experiment.
+
+Run GPE/GPI on task (1, -1) with w obtained by regression.
+
+
+For example, first train a keyboard:
+
+python3 train_keyboard.py -- --logtostderr --policy_weights_name=12 \
+  --export_path=/tmp/option_keyboard/keyboard
+
+
+Then, evaluate the keyboard with w by regression.
+
+python3 run_regressed_w_fig4b.py -- --logtostderr \
+  --keyboard_path=/tmp/option_keyboard/keyboard_12/tfhub
+"""
+
+from absl import app
+from absl import flags
+
+import numpy as np
+import tensorflow.compat.v1 as tf
+import tensorflow_hub as hub
+
+from option_keyboard import configs
+from option_keyboard import environment_wrappers
+from option_keyboard import experiment
+from option_keyboard import scavenger
+from option_keyboard import smart_module
+
+from option_keyboard.gpe_gpi_experiments import regressed_agent
+
+FLAGS = flags.FLAGS
+flags.DEFINE_integer("num_episodes", 4000, "Number of training episodes.")
+flags.DEFINE_integer("report_every", 5,
+                     "Frequency at which metrics are reported.")
+flags.DEFINE_string("keyboard_path", None, "Path to keyboard model.")
+flags.DEFINE_string("output_path", None, "Path to write out training curves.")
+
+
+def main(argv):
+  del argv
+
+  # Load the keyboard.
+  keyboard = smart_module.SmartModuleImport(hub.Module(FLAGS.keyboard_path))
+
+  # Create the task environment.
+  base_env_config = configs.get_fig4_task_config()
+  base_env = scavenger.Scavenger(**base_env_config)
+  base_env = environment_wrappers.EnvironmentWithLogging(base_env)
+
+  # Wrap the task environment with the keyboard.
+  additional_discount = 0.9
+  env = environment_wrappers.EnvironmentWithKeyboardDirect(
+      env=base_env,
+      keyboard=keyboard,
+      keyboard_ckpt_path=None,
+      additional_discount=additional_discount,
+      call_and_return=False)
+
+  # Create the player agent.
+  agent = regressed_agent.Agent(
+      batch_size=10,
+      optimizer_name="AdamOptimizer",
+      optimizer_kwargs=dict(learning_rate=3e-2,),
+      init_w=np.random.normal(size=keyboard.num_cumulants) * 0.1,
+  )
+
+  _, ema_returns = experiment.run(
+      env,
+      agent,
+      num_episodes=FLAGS.num_episodes,
+      report_every=FLAGS.report_every,
+      num_eval_reps=20)
+  if FLAGS.output_path:
+    experiment.write_returns_to_file(FLAGS.output_path, ema_returns)
+
+
+if __name__ == "__main__":
+  tf.disable_v2_behavior()
+  app.run(main)

option_keyboard/gpe_gpi_experiments/run_regressed_w_fig4c.py

@@ -27,7 +27,7 @@ python3 train_keyboard.py -- --logtostderr --policy_weights_name=12 \
 
 Then, evaluate the keyboard with w by regression.
 
-python3 run_regressed_w_fig4.py -- --logtostderr \
+python3 run_regressed_w_fig4c.py -- --logtostderr \
   --keyboard_path=/tmp/option_keyboard/keyboard_12/tfhub
 """
 
@@ -47,8 +47,11 @@ from option_keyboard import smart_module
 from option_keyboard.gpe_gpi_experiments import regressed_agent
 
 FLAGS = flags.FLAGS
-flags.DEFINE_integer("num_episodes", 1000, "Number of training episodes.")
+flags.DEFINE_integer("num_episodes", 100, "Number of training episodes.")
+flags.DEFINE_integer("report_every", 1,
+                     "Frequency at which metrics are reported.")
 flags.DEFINE_string("keyboard_path", None, "Path to keyboard model.")
+flags.DEFINE_string("output_path", None, "Path to write out training curves.")
 
 
 def main(argv):
@@ -75,16 +78,18 @@ def main(argv):
   agent = regressed_agent.Agent(
       batch_size=10,
       optimizer_name="AdamOptimizer",
-      optimizer_kwargs=dict(learning_rate=1e-1,),
+      optimizer_kwargs=dict(learning_rate=3e-2,),
       init_w=np.random.normal(size=keyboard.num_cumulants) * 0.1,
   )
 
-  experiment.run(
+  _, ema_returns = experiment.run(
       env,
       agent,
       num_episodes=FLAGS.num_episodes,
-      report_every=2,
+      report_every=FLAGS.report_every,
       num_eval_reps=100)
+  if FLAGS.output_path:
+    experiment.write_returns_to_file(FLAGS.output_path, ema_returns)
 
 
 if __name__ == "__main__":

option_keyboard/gpe_gpi_experiments/run_regressed_w_with_phi_fig4c.py

@@ -35,7 +35,7 @@ python3 train_keyboard_with_phi.py -- --logtostderr \
 
 Finally, evaluate the keyboard with w by regression.
 
-python3 run_regressed_w_with_phi_fig4b.py -- --logtostderr \
+python3 run_regressed_w_with_phi_fig4c.py -- --logtostderr \
   --phi_model_path=/tmp/option_keyboard/phi_model_3d \
   --keyboard_path=/tmp/option_keyboard/keyboard_3d/tfhub
 """
@@ -56,9 +56,12 @@ from option_keyboard import smart_module
 from option_keyboard.gpe_gpi_experiments import regressed_agent
 
 FLAGS = flags.FLAGS
-flags.DEFINE_integer("num_episodes", 1000, "Number of training episodes.")
+flags.DEFINE_integer("num_episodes", 100, "Number of training episodes.")
+flags.DEFINE_integer("report_every", 1,
+                     "Frequency at which metrics are reported.")
 flags.DEFINE_string("phi_model_path", None, "Path to phi model.")
 flags.DEFINE_string("keyboard_path", None, "Path to keyboard model.")
+flags.DEFINE_string("output_path", None, "Path to write out training curves.")
 
 
 def main(argv):
@@ -88,16 +91,18 @@ def main(argv):
   agent = regressed_agent.Agent(
       batch_size=10,
       optimizer_name="AdamOptimizer",
-      optimizer_kwargs=dict(learning_rate=1e-1,),
+      optimizer_kwargs=dict(learning_rate=3e-2,),
       init_w=np.random.normal(size=keyboard.num_cumulants) * 0.1,
   )
 
-  experiment.run(
+  _, ema_returns = experiment.run(
       env,
       agent,
       num_episodes=FLAGS.num_episodes,
-      report_every=2,
+      report_every=FLAGS.report_every,
       num_eval_reps=100)
+  if FLAGS.output_path:
+    experiment.write_returns_to_file(FLAGS.output_path, ema_returns)
 
 
 if __name__ == "__main__":

option_keyboard/gpe_gpi_experiments/run_true_w_fig4.py

@@ -30,11 +30,14 @@ python3 run_true_w_fig4.py -- --logtostderr \
   --keyboard_path=/tmp/option_keyboard/keyboard_12/tfhub
 """
 
+import csv
+
 from absl import app
 from absl import flags
 
 import numpy as np
 import tensorflow.compat.v1 as tf
+from tensorflow.compat.v1.io import gfile
 import tensorflow_hub as hub
 
 from option_keyboard import configs
@@ -48,6 +51,7 @@ from option_keyboard.gpe_gpi_experiments import regressed_agent
 FLAGS = flags.FLAGS
 flags.DEFINE_integer("num_episodes", 1000, "Number of training episodes.")
 flags.DEFINE_string("keyboard_path", None, "Path to keyboard model.")
+flags.DEFINE_string("output_path", None, "Path to write out returns.")
 
 
 def main(argv):
@@ -86,6 +90,13 @@ def main(argv):
       f"Avg. return over {FLAGS.num_episodes} episodes is {np.mean(returns)}")
   tf.logging.info("#" * 80)
 
+  if FLAGS.output_path:
+    with gfile.GFile(FLAGS.output_path, "w") as file:
+      writer = csv.writer(file, delimiter=" ", quoting=csv.QUOTE_MINIMAL)
+      writer.writerow(["return"])
+      for val in returns:
+        writer.writerow([val])
+
 
 if __name__ == "__main__":
   tf.disable_v2_behavior()

option_keyboard/gpe_gpi_experiments/run_true_w_fig6.py

@@ -26,15 +26,18 @@ python3 train_keyboard.py -- --logtostderr --policy_weights_name=12
 
 Then, evaluate the keyboard with a fixed w.
 
-python3 run_true_w_fig4.py -- --logtostderr \
+python3 run_true_w_fig6.py -- --logtostderr \
   --keyboard_path=/tmp/option_keyboard/keyboard_12/tfhub
 """
 
+import csv
+
 from absl import app
 from absl import flags
 
 import numpy as np
 import tensorflow.compat.v1 as tf
+from tensorflow.compat.v1.io import gfile
 import tensorflow_hub as hub
 
 from option_keyboard import configs
@@ -48,7 +51,8 @@ from option_keyboard.gpe_gpi_experiments import regressed_agent
 FLAGS = flags.FLAGS
 flags.DEFINE_integer("num_episodes", 1000, "Number of training episodes.")
 flags.DEFINE_string("keyboard_path", None, "Path to keyboard model.")
-flags.DEFINE_list("test_w", [], "The w to test.")
+flags.DEFINE_list("test_w", None, "The w to test.")
+flags.DEFINE_string("output_path", None, "Path to write out returns.")
 
 
 def main(argv):
@@ -87,6 +91,13 @@ def main(argv):
       f"Avg. return over {FLAGS.num_episodes} episodes is {np.mean(returns)}")
   tf.logging.info("#" * 80)
 
+  if FLAGS.output_path:
+    with gfile.GFile(FLAGS.output_path, "w") as file:
+      writer = csv.writer(file, delimiter=" ", quoting=csv.QUOTE_MINIMAL)
+      writer.writerow(["return"])
+      for val in returns:
+        writer.writerow([val])
+
 
 if __name__ == "__main__":
   tf.disable_v2_behavior()

option_keyboard/gpe_gpi_experiments/train_phi_model.py

@@ -139,10 +139,8 @@ def main(argv):
     tasks = [
         [1.0, 0.0],
         [0.0, 1.0],
-        [-1.0, 0.0],
+        [1.0, 1.0],
-        [0.0, -1.0],
+        [-1.0, 1.0],
-        [0.7, 0.3],
-        [-0.3, -0.7],
     ]
 
   if FLAGS.normalisation == "L1":

option_keyboard/run_dqn.py

@@ -29,6 +29,9 @@ from option_keyboard import scavenger
 
 FLAGS = flags.FLAGS
 flags.DEFINE_integer("num_episodes", 10000, "Number of training episodes.")
+flags.DEFINE_integer("report_every", 200,
+                     "Frequency at which metrics are reported.")
+flags.DEFINE_string("output_path", None, "Path to write out training curves.")
 
 
 def main(argv):
@@ -53,7 +56,13 @@ def main(argv):
       optimizer_name="AdamOptimizer",
       optimizer_kwargs=dict(learning_rate=3e-4,))
 
-  experiment.run(env, agent, num_episodes=FLAGS.num_episodes)
+  _, ema_returns = experiment.run(
+      env,
+      agent,
+      num_episodes=FLAGS.num_episodes,
+      report_every=FLAGS.report_every)
+  if FLAGS.output_path:
+    experiment.write_returns_to_file(FLAGS.output_path, ema_returns)
 
 
 if __name__ == "__main__":

option_keyboard/run_ok.py

@@ -36,7 +36,10 @@ FLAGS = flags.FLAGS
 flags.DEFINE_integer("num_episodes", 10000, "Number of training episodes.")
 flags.DEFINE_integer("num_pretrain_episodes", 20000,
                      "Number of pretraining episodes.")
+flags.DEFINE_integer("report_every", 200,
+                     "Frequency at which metrics are reported.")
 flags.DEFINE_string("keyboard_path", None, "Path to pretrained keyboard model.")
+flags.DEFINE_string("output_path", None, "Path to write out training curves.")
 
 
 def main(argv):
@@ -84,7 +87,13 @@ def main(argv):
       optimizer_name="AdamOptimizer",
       optimizer_kwargs=dict(learning_rate=3e-4,))
 
-  experiment.run(env, agent, num_episodes=FLAGS.num_episodes)
+  _, ema_returns = experiment.run(
+      env,
+      agent,
+      num_episodes=FLAGS.num_episodes,
+      report_every=FLAGS.report_every)
+  if FLAGS.output_path:
+    experiment.write_returns_to_file(FLAGS.output_path, ema_returns)
 
 
 if __name__ == "__main__":

option_keyboard/smart_module.py

@@ -17,11 +17,10 @@
 """Smart module export/import utilities."""
 
 import inspect
-import os
 import pickle
-import shutil
 
 import tensorflow.compat.v1 as tf
+from tensorflow.compat.v1.io import gfile
 import tensorflow_hub as hub
 import tree as nest
 import wrapt
@@ -164,9 +163,9 @@ class SmartModuleExport(object):
         module_session.run(
             assign_ops, feed_dict=dict(zip(assign_phs, module_weights)))
 
-        if overwrite and os.path.exists(path):
+        if overwrite and gfile.exists(path):
-          shutil.rmtree(path)
+          gfile.rmtree(path)
-        os.makedirs(path)
+        gfile.makedirs(path)
         hub_module.export(path, module_session)