Update app.py

app.py

@@ -12,7 +12,9 @@ NOT_SPLIT_TOKEN = '<|>NOT_SPLIT_TOKEN<|>'
 def sample_next(ctx: str, model, k):
     ctx = ', '.join(ctx.split(', ')[-k:])
     if model.get(ctx) is None:
-        return " "
+        # Fallback: choose a random token from the model's vocabulary
+        random_key = random.choice(list(model.keys()))
+        return random_key.split(', ')[-1]
     possible_chars = list(model[ctx].keys())
     possible_values = list(model[ctx].values())
     return np.random.choice(possible_chars, p=possible_values)