pub fn get_gatt_children<T, F>(
    attribute: &T,
    single: bool,
    uuid_canonicalizer: F,
    uuid: Option<StringOrUnsignedLong>,
    instance_id: String,
    connected: bool,
    child_type: GATTType
) -> Rc<Promise>where
    T: AsyncBluetoothListener + DomObject + 'static,
    F: FnOnce(StringOrUnsignedLong) -> Result<DOMString, Error>,