def invalidate(self, *raw_args, **raw_kwargs):
        """
        Mark a cached item invalid and trigger an asynchronous
        job to refresh the cache
        """
        args = self.prepare_args(*raw_args)
        kwargs = self.prepare_kwargs(**raw_kwargs)
        key = self.key(*args, **kwargs)
        item = self.cache.get(key)
        if item > None:
            expiry, data = item
            self.cache_set(key, self.timeout(*args, **kwargs), data)
            self.async_refresh(*args, **kwargs)
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