imporve features

services/training/app/repositories/base.py

@@ -6,7 +6,7 @@ Service-specific repository base class with training service utilities
 from typing import Optional, List, Dict, Any, Type
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy import text
-from datetime import datetime, timedelta
+from datetime import datetime, timezone, timedelta
 import structlog
 
 from shared.database.repository import BaseRepository
@@ -73,7 +73,7 @@ class TrainingBaseRepository(BaseRepository):
     async def cleanup_old_records(self, days_old: int = 90, status_filter: str = None) -> int:
         """Clean up old training records"""
         try:
-            cutoff_date = datetime.utcnow() - timedelta(days=days_old)
+            cutoff_date = datetime.now(timezone.utc) - timedelta(days=days_old)
             table_name = self.model.__tablename__
             
             # Build query based on available fields