def _load_tracker_file_etag(self):
        f = None
        try:
            f = open(self.tracker_file_name, 'r')
            etag_line = f.readline()
            m = re.search(self.ETAG_REGEX, etag_line)
            if m:
                self.etag_value_for_current_download = m.group(1)
            else:
                print('Couldn\'t read etag in tracker file (%s). Restarting '
                      'download from scratch.' % self.tracker_file_name)
        except __HOLE__, e:
            # Ignore non-existent file (happens first time a download
            # is attempted on an object), but warn user for other errors.
            if e.errno != errno.ENOENT:
                # Will restart because
                # self.etag_value_for_current_download == None.
                print('Couldn\'t read URI tracker file (%s): %s. Restarting '
                      'download from scratch.' %
                      (self.tracker_file_name, e.strerror))
        finally:
            if f:
                f.close()
dataset/ETHPy150Open darcyliu/storyboard/boto/s3/resumable_download_handler.py/ResumableDownloadHandler._load_tracker_file_etag