docs: def p_duration_number_duration_unit_duration(self, p):
          'duration : NUMBER DURATION_UNIT duration'
          logger.debug(
              'duration = number %s, duration unit %s, duration %s', p[1], p[2],
              p[3])
          duration = Duration.from_quantity_unit(p[1], p[2])
          p[0] = duration + p[3]