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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 _memcache_key(self, timestamped=False):
 """Makes a key suitable as a memcache entry."""

        request = tuple(map(str, self.package_requests))
        repo_ids = []
        for path in self.package_paths:
            repo = package_repository_manager.get_repository(path)
            repo_ids.append(repo.uid)

        t = ["resolve",
             request,
             tuple(repo_ids),
             self.package_filter_hash,
             self.package_orderers_hash,
             self.building,
             config.prune_failed_graph]

        if timestamped and self.timestamp:
            t.append(self.timestamp)

        return str(tuple(t))