fix time table

app/models/reservation.py

@@ -27,6 +27,11 @@ class Reservation(db.Model):
     created_at = db.Column(db.DateTime, default=datetime.utcnow)
     updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
     
+# Relationships
+    classroom = db.relationship('Classroom', backref=db.backref('reservation_list', lazy=True, cascade='all, delete-orphan'))
+    commission = db.relationship('Commission', backref=db.backref('reservation_list', lazy=True, cascade='all, delete-orphan'))
+    # User already defines the relationship back to reservation
+    
     def to_dict(self):
         """Convert reservation to dictionary"""
         return {