code: def test_engine_per_bind(app: Flask, model_class: t.Any) -> None:
      app.config["SQLALCHEMY_BINDS"] = {"a": "sqlite://"}
      db = SQLAlchemy(app, model_class=model_class)
      assert db.engines["a"] is not db.engine
  
imports: from __future__ import annotations
  import os.path
  import typing
  import unittest.mock
  import pytest
  import sqlalchemy
  import sqlalchemy.pool
  from flask import Flask
  from flask_sqlalchemy import SQLAlchemy
label_desc: Use image node_id 2 for calling a global function with example usage: test_engine_per_bind(app, model_class) without return types