Lateasusual

import bpy
from bpy.types import Operator, DATA_PT_shape_keys

bl_info = {
    "name": "Shape key mirror",
    "description": "",
    "author": "Lateasusual",
    "version": (1, 0, 0),
    "blender": (2, 81, 0),
    "location": "Properties > Mesh > Shape Keys",

Lateasusual

import imgui
from sys import _getframe, settrace

class Panel:
    """
    This is... not a particularly *useful* example, but it allows us to have one Panel class which can be used for drawing *without* inheritance. See below for examples
    """

    class Closed(Exception):
        ...

Lateasusual

@tool
extends EditorScenePostImport

class MeshInstanceList:
	var mesh: Mesh
	var aabb: AABB
	var transforms: Array

# Converts geometry node instances into MultiMeshInstances
func gn_instances_to_mm(parent: Node, scene: Node):