How to use the arsenic.actions.Keyboard function in arsenic

keyboard = Keyboard()
    canvas = await session.get_element('#canvas')
    ctx = (
        pytest.raises(OperationNotSupported)
        if
        isinstance(session, CompatSession)
        else
        null_context
    )
    await session.get('/actions/')

    output = await session.wait_for_element(5, '#output')
    assert '' == await output.get_text()

    mouse = Mouse()
    keyboard = Keyboard()
    canvas = await session.get_element('#canvas')

    # keyboard actions cannot be emulated in non-w3c drivers
    ctx = (
        pytest.raises(OperationNotSupported)
        if
        isinstance(session, CompatSession)
        else
        null_context()
    )

    with ctx:
        actions = chain(
            mouse.move_to(canvas),
            mouse.down() & keyboard.down('a'),
            mouse.move_by(10, 20) & keyboard.up('a'),

async def test_chained_actions(session):
    if isinstance(session.browser, Firefox) and isinstance(session.service, Remote):
        pytest.xfail('remote firefox actions do not work')

    async def check(actions, expected):
        await session.perform_actions(actions)
        output = await session.get_element('#output')
        assert expected == await output.get_text()

    await session.get('/actions/')
    output = await session.wait_for_element(5, '#output')
    assert '' == await output.get_text()
    mouse = Mouse()
    keyboard = Keyboard()
    canvas = await session.get_element('#canvas')
    ctx = (
        pytest.raises(OperationNotSupported)
        if
        isinstance(session, CompatSession)
        else
        null_context
    )
    await session.get('/actions/')

    output = await session.wait_for_element(5, '#output')
    assert '' == await output.get_text()

    mouse = Mouse()
    keyboard = Keyboard()
    canvas = await session.get_element('#canvas')

async def check(actions, expected):
        await session.perform_actions(actions)
        output = await session.get_element("#output")
        assert expected == await output.get_text()

    await session.get("/actions/")
    output = await session.wait_for_element(5, "#output")
    assert "" == await output.get_text()

    await session.get("/actions/")

    output = await session.wait_for_element(5, "#output")
    assert "" == await output.get_text()

    mouse = Mouse()
    keyboard = Keyboard()
    canvas = await session.get_element("#canvas")

    # keyboard actions cannot be emulated in non-w3c drivers
    ctx = (
        pytest.raises(OperationNotSupported)
        if isinstance(session, CompatSession)
        else null_context()
    )

    with ctx:
        actions = chain(
            mouse.move_to(canvas),
            mouse.down() & keyboard.down("a"),
            mouse.move_by(10, 20) & keyboard.up("a"),
            mouse.up(),
        )