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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 _log_progress(self, bytes_downloaded):
 """Logs progress information about ongoing module download. Args: bytes_downloaded: Number of bytes downloaded. """

    self._total_bytes_downloaded += bytes_downloaded
    now = time.time()
    if (self._interactive_mode() or
        now - self._last_progress_msg_print_time > 15):
      # Print progress message every 15 secs or if interactive progress
      # tracking is enabled.
      self._print_download_progress_msg(
          "Downloading %s: %s" % (self._url,
                                  tf_utils.bytes_to_readable_str(
                                      self._total_bytes_downloaded, True)))
      self._last_progress_msg_print_time = now