Update app.py

app.py

@@ -7,6 +7,7 @@ from slack_sdk import WebClient
 from slack_sdk.errors import SlackApiError
 import aiojobs
 import asyncio
+import re
 from datetime import datetime, timedelta
 from apscheduler.executors.pool import ThreadPoolExecutor
 from apscheduler.schedulers.background import BackgroundScheduler