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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_config(logdir):
 # pylint: disable=missing-raises-doc """Load a configuration from the log directory. Args: logdir: The logging directory containing the configuration file. Raises: IOError: The logging directory does not contain a configuration file. Returns: Configuration object. """

  config_path = logdir and os.path.join(logdir, 'config.yaml')
  if not config_path or not tf.gfile.Exists(config_path):
    message = (
        'Cannot resume an existing run since the logging directory does not '
        'contain a configuration file.')
    raise IOError(message)
  with tf.gfile.FastGFile(config_path, 'r') as file_:
    config = yaml.load(file_, Loader=yaml.Loader)
  message = 'Resume run and write summaries and checkpoints to {}.'
  tf.logging.info(message.format(config.logdir))
  return config