Update app.py

app.py

@@ -5,6 +5,8 @@ review_model = TFGPT2LMHeadModel.from_pretrained("kmkarakaya/turkishReviews-ds")
 review_tokenizer = AutoTokenizer.from_pretrained("kmkarakaya/turkishReviews-ds")
 
 def generate_review(prompt):
+  if prompt is None:
+     prompt = " "
   input_ids = review_tokenizer.encode(prompt, return_tensors='tf')
   context_length = 40
   output = review_model.generate(