code: def __get_enabled_heuristics(self, url):
          
          if url in self.__sites_heuristics:
              return self.__sites_heuristics[url]
  
          site = self.__sites_object[url]
          heuristics = dict(self.cfg_heuristics["enabled_heuristics"])
          if "overwrite_heuristics" in site:
              for heuristic, value in site["overwrite_heuristics"].items():
                  if value is False and heuristic in heuristics:
                      del heuristics[heuristic]
                  else:
                      heuristics[heuristic] = value
          self.__sites_heuristics[site["url"]] = heuristics
  
          self.log.debug(
              "Enabled heuristics for %s: %s", site["url"], heuristics
          )
  
          return heuristics
docs: Get the enabled heuristics for a site, merging the default and the
          overwrite together.
          The config will only be read once and the merged site-config will be
          cached.
  
          :param str url: The url to get the heuristics for.