export: fixed a bug introduced in version 3.0.0b28

python/obitools3/uri/decode.pyx

@@ -276,9 +276,9 @@ def open_uri(uri,
             iseq = urib
             objclass = bytes
     else:  # TODO update uopen to be able to write? 
-        if urip.path == b'-':
+        if not urip.path or urip.path == b'-':
             file = sys.stdout.buffer
-        elif urip.path :
+        else:
             file = open(urip.path, 'wb')
 
     if file is not None: