You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: axis.rs
    path of file: ./repos/bevy/crates/bevy_input/src
    
    the code of the file until where you have to start completion: //! The generic axis type.

use bevy_ecs::system::Resource;
use bevy_utils::HashMap;
use std::hash::Hash;

/// Stores the position data of the input devices of type `T`.
///
/// The values are stored as `f32`s, using [`Axis::set`].
/// Use [`Axis::get`] to retrieve the value clamped between [`Axis::MIN`] and [`Axis::MAX`]
/// inclusive, or unclamped using [`Axis::get_unclamped`].
#[derive(Debug, Resource)]
pub struct Axis<T> {
    /// The position data of the input devices.
    a
    
    fn test_axis_devices() {
        let mut axis = Axis::<GamepadButton>::default();
        assert_eq!(axis.devices().count(), 0);

        axis.set(
            GamepadButton::new(Gamepad::new(1), GamepadButtonType::RightTrigger),
            0.1,
        );
        assert_eq!(axis.devices().count(), 1);

        axis.set(
            GamepadButton::new(Gamepad::new(1), GamepadButtonType::LeftTrigger),
            0.5,
        );
        assert_eq!(axis.devices().count(), 2);

        axis.set(
            GamepadButton::new(Gamepad::new(1), GamepadButtonType::RightTrigger),
            -0.1,
        );
        assert_eq!(axis.devices().count(), 2);

        axis.remove(GamepadButton::new(
            Gamepad::new(1),
            GamepadButtonType::RightTrigger,
        ));
        assert_eq!(axis.devices().count(), 1);
    }