Update app.py

app.py

@@ -10,14 +10,16 @@ class ChatBot:
     def __init__(self):    
         self.history = []    
   
-    def predict(self, input):        
-        new_user_input_ids = tokenizer.encode(input + tokenizer.eos_token, return_tensors="pt")        
-        flat_history = [item for sublist in self.history for item in sublist]      
-        bot_input_ids = torch.cat([torch.tensor(flat_history), new_user_input_ids], dim=-1) if self.history else new_user_input_ids        
-        chat_history_ids = model.generate(bot_input_ids, max_length=2000, pad_token_id=tokenizer.eos_token_id)        
-        self.history.append(chat_history_ids[:, bot_input_ids.shape[-1]:].tolist()[0])        
-        response = tokenizer.decode(chat_history_ids[:, bot_input_ids.shape[-1]:][0], skip_special_tokens=True)        
-        return response  
+    def predict(self, input):          
+        new_user_input_ids = tokenizer.encode(input + tokenizer.eos_token, return_tensors="pt")          
+        flat_history = [item for sublist in self.history for item in sublist]     
+        flat_history_tensor = torch.tensor(flat_history).unsqueeze(dim=0)  # convert list to 2-D tensor  
+        bot_input_ids = torch.cat([flat_history_tensor, new_user_input_ids], dim=-1) if self.history else new_user_input_ids          
+        chat_history_ids = model.generate(bot_input_ids, max_length=2000, pad_token_id=tokenizer.eos_token_id)          
+        self.history.append(chat_history_ids[:, bot_input_ids.shape[-1]:].tolist()[0])          
+        response = tokenizer.decode(chat_history_ids[:, bot_input_ids.shape[-1]:][0], skip_special_tokens=True)          
+    return response    
+
   
 bot = ChatBot()