Update app.py

app.py

@@ -35,7 +35,7 @@ def get_birth_stone(month:str)-> str: #it's import to specify the return type
         
     month = month
     birthstone = birthstones.get(month, "Unknown")
-    if birthstone in image_urls:
+    if birthstone in birthstones:
         response = birthstone
     else:
         response = "Unknown"