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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 _server_property(self, attr_name):
 """An attribute of the current server's description. If the client is not connected, this will block until a connection is established or raise ServerSelectionTimeoutError if no server is available. Not threadsafe if used multiple times in a single method, since the server may change. In such cases, store a local reference to a ServerDescription first, then use its properties. """

        server = self._topology.select_server(
            writable_server_selector)

        return getattr(server.description, attr_name)