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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 set(self, key, val, timeout=None, using=None):
 """ Set will be using the generational key, so if another thread bumps this key, the localstore version will still be invalid. If the key is bumped during a transaction it will be new to the global cache on commit, so it will still be a bump. """

        if timeout is None:
            timeout = self.timeout
        if self.is_managed(using=using) and self._patched_var:
            self.local[key] = val
        else:
            self.cache_backend.set(key, val, timeout)