docs: def str_to_datetime(timestamp, str_format='%Y-%m-%d_%H:%M:%S.fff'):
      """
      :param str_format:
      :param timestamp: str of the timestamp
      :return:          datetime
      """
      date_time = datetime.strptime(timestamp.split('.')[0],
                                    str_format.split('.')[0])
      if '.' in timestamp:
          date_time += timedelta(seconds=eval('0.%s' % timestamp.split('.')[1]))
      if DEFAULT_TIMEZONE_AWARE:
          date_time = date_time.replace(
              tzinfo=psycopg2.tz.FixedOffsetTimezone(
                  offset=DEFAULT_TIMEZONE * 60, name=None))
      return date_time