Update app.py

app.py

@@ -167,6 +167,8 @@ if uploaded_file is not None:
     # Initialize embeddings and vectorstore
     embedding_model = GoogleGenerativeAIEmbeddings(model="models/embedding-001")
     db = Chroma.from_documents(chunks, embedding_model, persist_directory="./chroma_db")
+    if not os.path.exists("./chroma_db"):
+        os.makedirs("./chroma_db")
 
     db.persist()