Feat/fix ops trace (#5672)

Co-authored-by: takatost <takatost@gmail.com>

api/app.py

@@ -26,7 +26,6 @@ from werkzeug.exceptions import Unauthorized
 from commands import register_commands
 
 # DO NOT REMOVE BELOW
-from events import event_handlers
 from extensions import (
     ext_celery,
     ext_code_based_extension,
@@ -43,7 +42,6 @@ from extensions import (
 from extensions.ext_database import db
 from extensions.ext_login import login_manager
 from libs.passport import PassportService
-from models import account, dataset, model, source, task, tool, tools, web
 from services.account_service import AccountService
 
 # DO NOT REMOVE ABOVE