Update app.py

app.py

@@ -14,6 +14,8 @@ from langchain.vectorstores import Chroma
 from dotenv import load_dotenv, find_dotenv
 _ = load_dotenv(find_dotenv())
 
+global vectordb
+
 #openai.api_key = os.environ["OPENAI_API_KEY"]
 
 template = """Use the following pieces of context to answer the question at the end. If you don't know the answer, just say that you don't know, don't try to make up