<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def set_many(self, values, expire=0, noreply=None):
 """ A convenience function for setting multiple values. Args: values: dict(str, str), a dict of keys and values, see class docs for details. expire: optional int, number of seconds until the item is expired from the cache, or zero for no expiry (the default). noreply: optional bool, True to not wait for the reply (defaults to self.default_noreply). Returns: Returns a list of keys that failed to be inserted. If noreply is True, always returns empty list. """

        if noreply is None:
            noreply = self.default_noreply
        result = self._store_cmd(b'set', values, expire, noreply)
        return [k for k, v in six.iteritems(result) if not v]