foofoozula.py

import bpy

class Rotator(bpy.types.Operator):
    bl_idname = "pieops.set_manip"
    bl_label = "Set the manip"

    def execute(self, context):
        try:
            context.space_data.transform_manipulators = {'ROTATE'}
        except:
            print('failed to set')
        return {'FINISHED'}


class NewPie(bpy.types.Menu):
    bl_idname = 'kwanza'
    bl_label = "Select Mode"

    def draw(self, context):
        layout = self.layout

        pie = layout.menu_pie()
        pie.operator("mesh.primitive_cube_add")
        pie.operator("pieops.set_manip", text="ROTATE")


addon_keymaps = []


def register():
    bpy.utils.register_class(Rotator)
    bpy.utils.register_class(NewPie)    

    wm = bpy.context.window_manager
    kc = wm.keyconfigs.addon
    km = kc.keymaps.new('3D View', space_type='VIEW_3D', region_type='WINDOW')
    keymaps = km.keymap_items

    new_shortcut = keymaps.new("wm.call_menu_pie", "SEMI_COLON", "PRESS", shift=True)
    new_shortcut.properties.name = 'kwanza'
    addon_keymaps.append((km, new_shortcut))


def unregister():
    bpy.utils.unregister_class(Rotator)
    bpy.utils.unregister_class(NewPie)    

    for km, shortcut in addon_keymaps:
        km.keymap_items.remove(shortcut)
    addon_keymaps.clear()


if __name__ == "__main__":
    register()