How to use the ipyleaflet.leaflet.UILayer function in ipyleaflet

def on_mouseup(self, callback, remove=False):
        self._mouseup_callbacks.register_callback(callback, remove=remove)

    def on_mouseover(self, callback, remove=False):
        self._mouseover_callbacks.register_callback(callback, remove=remove)

    def on_mouseout(self, callback, remove=False):
        self._mouseout_callbacks.register_callback(callback, remove=remove)


class UILayer(Layer):
    _view_name = Unicode('LeafletUILayerView').tag(sync=True)
    _model_name = Unicode('LeafletUILayerModel').tag(sync=True)


class Icon(UILayer):
    _view_name = Unicode('LeafletIconView').tag(sync=True)
    _model_name = Unicode('LeafletIconModel').tag(sync=True)

    icon_url = Unicode('').tag(sync=True, o=True)
    shadow_url = Unicode(None, allow_none=True).tag(sync=True, o=True)
    icon_size = Tuple((10, 10), allow_none=True).tag(sync=True, o=True)
    shadow_size = Tuple((10, 10), allow_none=True).tag(sync=True, o=True)
    icon_anchor = Tuple((0, 0), allow_none=True).tag(sync=True, o=True)
    shadow_anchor = Tuple((0, 0), allow_none=True).tag(sync=True, o=True)
    popup_anchor = Tuple((0, 0), allow_none=True).tag(sync=True, o=True)


class AwesomeIcon(UILayer):
    _view_name = Unicode('LeafletAwesomeIconView').tag(sync=True)
    _model_name = Unicode('LeafletAwesomeIconModel').tag(sync=True)

class Icon(UILayer):
    _view_name = Unicode('LeafletIconView').tag(sync=True)
    _model_name = Unicode('LeafletIconModel').tag(sync=True)

    icon_url = Unicode('').tag(sync=True, o=True)
    shadow_url = Unicode(None, allow_none=True).tag(sync=True, o=True)
    icon_size = Tuple((10, 10), allow_none=True).tag(sync=True, o=True)
    shadow_size = Tuple((10, 10), allow_none=True).tag(sync=True, o=True)
    icon_anchor = Tuple((0, 0), allow_none=True).tag(sync=True, o=True)
    shadow_anchor = Tuple((0, 0), allow_none=True).tag(sync=True, o=True)
    popup_anchor = Tuple((0, 0), allow_none=True).tag(sync=True, o=True)


class AwesomeIcon(UILayer):
    _view_name = Unicode('LeafletAwesomeIconView').tag(sync=True)
    _model_name = Unicode('LeafletAwesomeIconModel').tag(sync=True)

    name = Unicode('home').tag(sync=True)
    marker_color = Enum(
        values=['white', 'red', 'darkred', 'lightred', 'orange', 'beige', 'green', 'darkgreen', 'lightgreen', 'blue', 'darkblue', 'lightblue', 'purple', 'darkpurple', 'pink', 'cadetblue', 'white', 'gray', 'lightgray', 'black'],
        default_value='blue'
    ).tag(sync=True)
    icon_color = Color('white').tag(sync=True)
    spin = Bool(False).tag(sync=True)


class Marker(UILayer):
    _view_name = Unicode('LeafletMarkerView').tag(sync=True)
    _model_name = Unicode('LeafletMarkerModel').tag(sync=True)

_move_callbacks = Instance(CallbackDispatcher, ())

    def __init__(self, **kwargs):
        super(Marker, self).__init__(**kwargs)
        self.on_msg(self._handle_leaflet_event)

    def _handle_leaflet_event(self, _, content, buffers):
        if content.get('event', '') == 'move':
            self._move_callbacks(**content)

    def on_move(self, callback, remove=False):
        self._move_callbacks.register_callback(callback, remove=remove)


class Popup(UILayer):
    _view_name = Unicode('LeafletPopupView').tag(sync=True)
    _model_name = Unicode('LeafletPopupModel').tag(sync=True)

    location = List(def_loc).tag(sync=True)
    child = Instance(
        DOMWidget, allow_none=True, default_value=None
    ).tag(sync=True, **widget_serialization)

    # Options
    min_width = Int(50).tag(sync=True, o=True)
    max_width = Int(300).tag(sync=True, o=True)
    max_height = Int(default_value=None, allow_none=True).tag(sync=True, o=True)
    auto_pan = Bool(True).tag(sync=True, o=True)
    auto_pan_padding_top_left = List(allow_none=True, default_value=None).tag(sync=True, o=True)
    auto_pan_padding_bottom_right = List(allow_none=True, default_value=None).tag(sync=True, o=True)
    auto_pan_padding = List([5, 5]).tag(sync=True, o=True)

class AwesomeIcon(UILayer):
    _view_name = Unicode('LeafletAwesomeIconView').tag(sync=True)
    _model_name = Unicode('LeafletAwesomeIconModel').tag(sync=True)

    name = Unicode('home').tag(sync=True)
    marker_color = Enum(
        values=['white', 'red', 'darkred', 'lightred', 'orange', 'beige', 'green', 'darkgreen', 'lightgreen', 'blue', 'darkblue', 'lightblue', 'purple', 'darkpurple', 'pink', 'cadetblue', 'white', 'gray', 'lightgray', 'black'],
        default_value='blue'
    ).tag(sync=True)
    icon_color = Color('white').tag(sync=True)
    spin = Bool(False).tag(sync=True)


class Marker(UILayer):
    _view_name = Unicode('LeafletMarkerView').tag(sync=True)
    _model_name = Unicode('LeafletMarkerModel').tag(sync=True)

    location = List(def_loc).tag(sync=True)
    opacity = Float(1.0, min=0.0, max=1.0).tag(sync=True)
    visible = Bool(True).tag(sync=True)
    icon = Union((Instance(Icon), Instance(AwesomeIcon)), allow_none=True, default_value=None).tag(sync=True, **widget_serialization)

    # Options
    z_index_offset = Int(0).tag(sync=True, o=True)
    draggable = Bool(True).tag(sync=True, o=True)
    keyboard = Bool(True).tag(sync=True, o=True)
    title = Unicode('').tag(sync=True, o=True)
    alt = Unicode('').tag(sync=True, o=True)
    rise_on_hover = Bool(False).tag(sync=True, o=True)
    rise_offset = Int(250).tag(sync=True, o=True)