Update plugins/button.py

plugins/button.py

@@ -43,8 +43,8 @@ async def youtube_dl_call_back(_bot, update):
     custom_file_name = (
         str(response_json.get("title")) + "_" + youtube_dl_format + "." + youtube_dl_ext
     )
-    youtube_dl_username = None
-    youtube_dl_password = None
+    youtube_dl_username = os.environ.get("YTU", None)
+    youtube_dl_password = os.environ.get("YTP", None)
 
     if "|" in youtube_dl_url:
         url_parts = youtube_dl_url.split("|")