def METHOD_NAME(dash_duo):
    lock = Lock()
    call_count = Value("i")
    app = Dash(__name__)
    app.layout = html.Div(
        [
            dcc.Input(id="input", value="dash"),
            html.Div(html.Div(id="output"), id="output-container"),
        ]
    )
    @app.callback(
        [
            Output("output", "children"),
            Output("output", "style"),
            Output("output", "className"),
        ],
        [Input("input", "value")],
    )
    def update_output(value):
        with lock:
            call_count.value += 1
            return [value, {"fontFamily": value}, value]
    dash_duo.start_server(app)
    dash_duo.wait_for_text_to_equal("#output-container", "dash")
    _html = dash_duo.find_element("#output-container").get_property("innerHTML")
    assert _html == (
        '<div id="output" class="dash" style="font-family: dash;">dash</div>'
    )
    assert call_count.value == 1
    for key in " hello":
        with lock:
            dash_duo.find_element("#input").send_keys(key)
    dash_duo.wait_for_text_to_equal("#output-container", "dash hello")
    _html = dash_duo.find_element("#output-container").get_property("innerHTML")
    assert _html == (
        '<div id="output" class="dash hello" '
        'style="font-family: &quot;dash hello&quot;;">dash hello</div>'
    )
    wait.until(lambda: call_count.value == 7, 3)