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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 flushall(self, async_op=False):
 """ Remove all keys from all databases. :param async_op: lets the entire dataset to be freed asynchronously. \ Defaults to False """

        if async_op:
            fut = self.execute(b'FLUSHALL', b'ASYNC')
        else:
            fut = self.execute(b'FLUSHALL')
        return wait_ok(fut)