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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __get_enabled_heuristics(self, url):
 """ 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. """

        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