Fix datetime error

app.py

@@ -1,6 +1,5 @@
 import gradio as gr
 import zipfile
-import os
 import datetime
 
 
@@ -14,7 +13,7 @@ def add_image(camera, gallery):
 
 
 def zip_gallery(gallery):
-    new_zip_name = f'{datetime.today()}.zip'
+    new_zip_name = f'{datetime.datetime.now().strftime("%Y_%m_%d_%H_%M_%S")}.zip'
     count = 0
     if not gallery:
         return gr.DownloadButton("Download", visible=False)