code: def test_middleware():
      client = TestClient(app, base_url="http://example.com")
      response = client.get("/")
      assert response.status_code == 200, response.text
      client = TestClient(app, base_url="http://subdomain.example.com")
      response = client.get("/")
      assert response.status_code == 200, response.text
      client = TestClient(app, base_url="http://invalidhost")
      response = client.get("/")
      assert response.status_code == 400, response.text
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_middleware() without return types