TThis should work

app.py

@@ -179,7 +179,7 @@ model.to(device)
 context = torch.zeros((1, 1), dtype=torch.long, device=device)
 
 def greet(start_character, number_of_tokens):
-    context[0][0] = encode(start_character)
+    context[0][0] = encode(start_character)[0]
     max_new_tokens = number_of_tokens
     return decode(model.generate(context, max_new_tokens=max_new_tokens)[0].tolist())