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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 remove_host(self, host_id):
 """Removes a host from the client. This only really useful for unittests. """

        with self._lock:
            rv = self._hosts.pop(host_id, None) is not None
            pool = self._pools.pop(host_id, None)
            if pool is not None:
                pool.disconnect()
            self._hosts_age += 1
            return rv