Format date for db

app.py

@@ -72,7 +72,7 @@ def toggle_pin(change_pin):
     if GPIO.input(change_pin) == 0:
         message += " off."
         if pins[change_pin]['on_time'] is not None:
-            start_time = pins[change_pin]['on_time']
+            start_time = str(pins[change_pin]['on_time'])
             elapsed = str(datetime.now() - start_time)
             date = datetime.strptime(start_time, '%Y-%m-%d').date()
             entry = DailyUsage(date=date, on_time=elapsed)