docs: def get_institute_usage(institute, start, end):
      """Return a tuple of cpu hours and number of jobs for an institute
      for a given period
  
      Keyword arguments:
      institute --
      start -- start date
      end -- end date
      """
      try:
          cache = InstituteCache.objects.get(
              institute=institute, date=datetime.date.today(),
              start=start, end=end)
          return cache.cpu_time, cache.no_jobs
      except InstituteCache.DoesNotExist:
          return 0, 0