Most complex type signature?

I want to see the most complex type signature (used in a real project, not created just-because).

Here is the one I encountered from iced:

pub fn application<State, Message, Theme, Renderer>(
    boot: impl Boot<State, Message>,
    update: impl Update<State, Message>,
    view: impl for<'a> self::View<'a, State, Message, Theme, Renderer>,
) -> Application<impl Program<State = State, Message = Message, Theme = Theme>>
where
    State: 'static,
    Message: Send + std::fmt::Debug + 'static,
    Theme: Default + theme::Base,
    Renderer: program::Renderer;