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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 _update_config(self):
 """ Call this when the server configuration file change """

        if self._local_server:
            server_config = Config.instance().get_section_config("Server")
            self._local_server.user = server_config.get("user")
            self._local_server.password = server_config.get("password")