text: # coding=utf-8
  # Copyright 2022 The TensorFlow Datasets Authors.
  #
  # 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"""Generate MNIST-like files, smaller and with random data."""
  
  import os
  
  from absl import app
  from absl import flags
  import numpy as np
  import tensorflow as tf
  
  from tensorflow_datasets.core.utils import py_utils
  from tensorflow_datasets.testing import test_utils
  
  flags.DEFINE_string("tfds_dir", py_utils.tfds_dir(),
                      "Path to tensorflow_datasets directory")
  FLAGS = flags.FLAGS
  
  
  def examples_dir():
    return os.path.join(FLAGS.tfds_dir, "testing", "test_data", "fake_examples")
  
  
  def mnist_dir(name):
    return os.path.join(examples_dir(), name)
  
  
  _TRAIN_DATA_FILENAME = "train-image"
  _TRAIN_LABELS_FILENAME = "train-label"
  _TEST_DATA_FILENAME = "test-image"
  _TEST_LABELS_FILENAME = "test-label"
  
  
  def make_images(num_images):
    return np.random.randint(256, size=(28 * 28 * num_images), dtype=np.uint8)
  
  
  def make_labels(num_labels):
    return np.random.randint(10, size=(num_labels), dtype=np.uint8)
  
  
  def write_image_file(filename, num_images):
    with tf.io.gfile.GFile(filename, "wb") as f:
      f.write(b"1" * 16)  # header
      f.write(make_images(num_images).tobytes())
  
  
  def write_label_file(filename, num_labels):
    with tf.io.gfile.GFile(filename, "wb") as f:
      f.write(b"1" * 8)  # header
      f.write(make_labels(num_labels).tobytes())
  
  
  def main(_):
    for mnist in ["mnist", "fashion_mnist", "kmnist", "emnist"]:
      output_dir = mnist_dir(mnist)
      test_utils.remake_dir(output_dir)
      write_image_file(os.path.join(output_dir, _TRAIN_DATA_FILENAME), 10)
      write_label_file(os.path.join(output_dir, _TRAIN_LABELS_FILENAME), 10)
      write_image_file(os.path.join(output_dir, _TEST_DATA_FILENAME), 2)
      write_label_file(os.path.join(output_dir, _TEST_LABELS_FILENAME), 2)
  
  
  if __name__ == "__main__":
    app.run(main)
  