code: def _update_response_location_header(self, resource):
          
          location = resource_to_url(resource, request=self.request)
          loc_hdr = ('Location', location)
          hdr_names = [hdr[0].upper() for hdr in self.request.response.headerlist]
          try:
              idx = hdr_names.index('LOCATION')
          except ValueError:
              self.request.response.headerlist.append(loc_hdr)
          else:
              # Replace existing location header.
              # FIXME: It is not clear under which conditions this happens, so
              #        we do not have a test for it yet.
              self.request.response.headerlist[idx] = loc_hdr
docs: Adds a new or replaces an existing Location header to the response
          headers pointing to the URL of the given resource.