def _apply_ssl_file_param(self, config: Union[Config, Dict[str, Any]], name: str) -> Union[str, None]:
        """Apply a given SSL related param to the request manager.

        :param config: Patroni YAML configuration.
        :param name: prefix of the Patroni SSL related setting name. Currently, supports these:

            * ``cert``: gets translated to ``certfile``
            * ``key``: gets translated to ``keyfile``

            Will attempt to fetch the requested key first from ``ctl`` section.

        :returns: value of ``ctl.*name*file`` if present, ``None`` otherwise.
        """
        value = self._get_ctl_value(config, name + 'file')
        self._apply_pool_param(name + '_file', value)
        return value
Apply a given SSL related param to the request manager.

        :param config: Patroni YAML configuration.
        :param name: prefix of the Patroni SSL related setting name. Currently, supports these:

            * ``cert``: gets translated to ``certfile``
            * ``key``: gets translated to ``keyfile``

            Will attempt to fetch the requested key first from ``ctl`` section.

        :returns: value of ``ctl.*name*file`` if present, ``None`` otherwise.
        
patroni/request.py