docs: def _metrics_get_endpoints(options):
      """ Determine the start and end dates based on user-supplied options. """
      if bool(options.start) ^ bool(options.end):
          log.error('--start and --end must be specified together')
          sys.exit(1)
  
      if options.start and options.end:
          start = options.start
          end = options.end
      else:
          end = datetime.utcnow()
          start = end - timedelta(options.days)
  
      return start, end