import unreal

# -- first let's acquire a global instance we'll need - ToolMenus
tool_menus = unreal.ToolMenus.get()

# -- now we need a handle on the main level editor toolbar instance.
# -- we can use ToolMenus' "find_menu" function for this.
toolbar = tool_menus.find_menu('LevelEditor.LevelEditorToolbar')

# -- now let's create a new menu entry
entry = unreal.ToolMenuEntryExtensions.init_menu_entry(
    # owner
    toolbar.menu_name,
    # name
    'MyPythonMenu',
    # label
    'My Python Menu',
    # tooltip
    'This is a custom python menu - you can do cool stuff with it!',
    # command_type
    unreal.ToolMenuStringCommandType.COMMAND,
    # custom command type - we don't need to use this
    '',
    # command string - normally this would be a python command, but we don't need this.
    ''
)

# -- now that we've created the entry, we can tell unreal it's supposed to be a combo button
entry.type = unreal.MultiBlockType.TOOL_BAR_COMBO_BUTTON

# -- and now we can add the button to the toolbar
toolbar.add_menu_entry('PythonExtensions', entry)

# -- as a final step we need to tell unreal to refresh all menus
tool_menus.refresh_all_widgets()