code: def test_ddcf002_clearable_false_multi(dash_duo):
      app = Dash(__name__)
      app.layout = html.Div(
          [
              dcc.Dropdown(
                  id="my-unclearable-dropdown",
                  options=[
                      {"label": "New York City", "value": "NYC"},
                      {"label": "Montreal", "value": "MTL"},
                      {"label": "San Francisco", "value": "SF"},
                  ],
                  value=["MTL", "SF"],
                  multi=True,
                  clearable=False,
              ),
              html.Div(
                  id="dropdown-value",
                  style={"height": "10px", "width": "10px"},
              ),
          ]
      )
  
      @app.callback(
          Output("dropdown-value", "children"),
          [Input("my-unclearable-dropdown", "value")],
      )
      def update_value(val):
          return ", ".join(val)
  
      dash_duo.start_server(app)
  
      dropdown = dash_duo.find_element("#my-unclearable-dropdown input")
      dropdown.send_keys(Keys.BACKSPACE)
      dropdown.send_keys(Keys.BACKSPACE)
      dash_duo.find_element("#dropdown-value").click()
  
      assert len(dash_duo.find_element("#dropdown-value").text) > 0
  
      assert dash_duo.get_logs() == []
  
label_desc: Use image node_id 2 for calling a global function with example usage: test_ddcf002_clearable_false_multi(dash_duo) and returns: str