Empty Pie Menu Blender

import bpy
from bpy.types import Menu, Operator

bl_info = {
    "name": "",
    "author": "",
    "version": (0, 0, 0, 1),
    "description": "",
    "blender": (2, 80, 0),
    "category": "3D view"
}

class VIEW3D_MT_PIE_template(Menu):
       # label is displayed at the center of the pie menu.
       bl_label = "Operations"
       bl_idname="mesh.mypie"

    def draw(self, context):

        layout = self.layout

        pie = layout.menu_pie()
        pie.operator("auto.smooth")

​
def register():
​       bpy.utils.register_class(VIEW3D_MT_PIE_template)
​       bpy.utils.register_class(AutoSmooth)
​

def unregister():
       bpy.utils.unregister_class(VIEW3D_MT_PIE_template)
       bpy.utils.unregister_class(AutoSmooth)

if __name__ == "__main__":
    register()

    bpy.ops.wm.call_menu_pie(name="VIEW3D_MT_PIE_template")


class AutoSmooth(Operator):
       bl_idname = "auto.smooth"
       bl_label = "AutoSmooth"

    def execute(self, context):
           bpy.ops.object.shade_smooth()
           bpy.context.object.data.use_auto_smooth = True

        return {'FINISHED'}