How to assign own functions to (pie) menus

In all the tutorials considering custom (pie) menus there’s always one operation assigned for a given (pie) menu slot.
But I want to make a (pie) menu that executes a series of operations by the click of one button.
So I don’t want a (pie) menu where I have a slot “Add Cube”, one slot “Toggle Edit Mode” and one slot “Subdivide”, like

class VIEW3D_PIE_template(Menu):
    # label is displayed at the center of the pie menu.
    bl_label = "Select Mode"

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

        pie = layout.menu_pie()
        
        pie.operator("bpy.ops.mesh.primitive_cube_add(size=2)")
        pie.operator("bpy.ops.object.editmode_toggle()")
        pie.operator("bpy.ops.mesh.subdivide()")
)

I want one automated process where I click the button and it will “add a cube, change to edit mode and subdevide the cube” all in one go, like

def foo():
    pie.operator("bpy.ops.mesh.primitive_cube_add(size=2)")
    pie.operator("bpy.ops.object.editmode_toggle()")
    pie.operator("bpy.ops.mesh.subdivide()")

class VIEW3D_PIE_template(Menu):
    # label is displayed at the center of the pie menu.
    bl_label = "Select Mode"

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

        pie = layout.menu_pie()
        
        pie.operator("foo()")
)

if that makes sense. I know the above example is technically wrong, it’s just to illustrate what my desired functionallity is.
Of course my usecase is a little more complex than this example but I wanna know about the general concept of using custom functions in a (pie) menu.

Since I haven’t found anything about that in the “Make a custom menu” tutorials and I don’t know what to search for any further, any help is appreciated.