Update app.py

app.py

@@ -8,7 +8,7 @@ st.title("ChatGPT-like Chatbot")
 base_url="https://api-inference.huggingface.co/models/"
 
 API_KEY = os.environ.get('HUGGINGFACE_API_KEY')
-headers = {"Authorization":"Bearer "+API_KEY}
+headers = {"Authorization":"Bearer " + str(API_KEY)}
 
 model_links ={
     "Mistral-7B":base_url+"mistralai/Mistral-7B-Instruct-v0.2",