Update app.py

app.py

@@ -6,7 +6,7 @@ from langchain.chains import create_retrieval_chain
 from langchain import HuggingFaceHub
 import os
 
-os.environ["HUGGINGFACEHUB_API_TOKEN"] = window.huggingface.variables.hf_token
+os.environ["HUGGINGFACEHUB_API_TOKEN"] = os.getenv('hf_token')
 
 llm = HuggingFaceHub(repo_id="tiiuae/falcon-7b-instruct",
                              model_kwargs={"max_length": 300, "max_new_tokens": 300})