docs: def process_request(self, request):
          """
          Redirects the current request if there is a matching Redirect model
          with the current request URL as the old_path field.
          """
          site = request.site
          cache_key = '{prefix}-{site}'.format(prefix=settings.REDIRECT_CACHE_KEY_PREFIX, site=site.domain)
          redirects = cache.get(cache_key)
          if redirects is None:
              redirects = {redirect.old_path: redirect.new_path for redirect in Redirect.objects.filter(site=site)}
              cache.set(cache_key, redirects, settings.REDIRECT_CACHE_TIMEOUT)
          redirect_to = redirects.get(request.path)
          if redirect_to:
              return redirect(redirect_to, permanent=True)