<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def retryable_writes_supported(self):
 """Checks if this server supports retryable writes."""

        return (
            self._ls_timeout_minutes is not None and
            self._server_type in (SERVER_TYPE.Mongos, SERVER_TYPE.RSPrimary))