Update app.py

app.py

@@ -35,13 +35,13 @@ def download_paper_and_embed(paper_arxiv_url, api_key):
         else:
             raise ValueError("Invalid arXiv URL")
         suffix = 'paper-dir/' + eprint_url.replace("https://arxiv.org/e-print/", "")
+        os.environ["OPENAI_API_KEY"] = api_key
         if not os.path.exists(suffix + "/docs.index"):
             create_vector_store(suffix, paper_text)
 
-        os.environ["OPENAI_API_KEY"] = api_key
+        
         vectorstore = get_vectorstore(suffix)
         qa_chain = VectorDBQAWithSourcesChain.from_llm(llm=OpenAI(temperature=0), vectorstore=vectorstore)
-        os.environ["OPENAI_API_KEY"] = ""
         return qa_chain
 
 chain = None