code: def parse(self):
          
          # Run the parser
          opt, arg = self.parser.parse_known_args(self.arguments)
          self.opt = opt
          self.arg = arg
          self.check()
  
          # Enable --all if no particular stat or group selected
          opt.all = not any([
              getattr(opt, stat.dest) or getattr(opt, group.dest)
              for group in self.sample_stats.stats
              for stat in group.stats])
  
          # Time period handling
          if opt.since is None and opt.until is None:
              opt.since, opt.until, period = did.base.Date.period(arg)
          else:
              opt.since = did.base.Date(opt.since or "1993-01-01")
              opt.until = did.base.Date(opt.until or "today")
              # Make the 'until' limit inclusive
              opt.until.date += delta(days=1)
              period = "given date range"
  
          # Validate the date range
          if not opt.since.date < opt.until.date:
              raise RuntimeError(
                  "Invalid date range ({0} to {1})".format(
                      opt.since, opt.until.date - delta(days=1)))
          header = "Status report for {0} ({1} to {2}).".format(
              period, opt.since, opt.until.date - delta(days=1))
  
          # Finito
          log.debug("Gathered options:")
          log.debug('options = {0}'.format(opt))
          return opt, header
docs: Parse the options.