def coupler_ring(
    gap: float = 0.2,
    radius: float = 5.0,
    length_x: float = 4.0,
    coupler90: ComponentFactory = coupler90function,
    bend: Optional[ComponentFactory] = None,
    coupler_straight: ComponentFactory = coupler_straight_function,
    cross_section: CrossSectionFactory = strip,
    bend_cross_section: Optional[CrossSectionFactory] = None,
    **kwargs