text: import tensorflow as tf
  
  
  def create_dataset_from_tasks(tasks, data_reader):
      """
      Returns a `tf.data.Dataset` from a list of `Task`s.
      """
  
      class _Generator:
          def __init__(self, tasks):
              self._tasks = tasks
              self._data_reader = data_reader
  
          def gen(self):
              for task in self._tasks:
                  for data in self._data_reader.read_records(task):
                      if data:
                          yield data
  
      generator = _Generator(tasks)
      dataset = tf.data.Dataset.from_generator(
          generator.gen, generator._data_reader.records_output_types
      )
      return dataset
  