From 6c9e45ad8c294e7291f5542186f82258e5c04fc8 Mon Sep 17 00:00:00 2001
From: RondeauG <38501935+RondeauG@users.noreply.github.com>
Date: Mon, 6 Nov 2023 15:33:41 -0500
Subject: [PATCH] Update xscen/catalog.py

Co-authored-by: Trevor James Smith <10819524+Zeitsperre@users.noreply.github.com>
---
 xscen/catalog.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xscen/catalog.py b/xscen/catalog.py
index 377f0279..bab8ca0d 100644
--- a/xscen/catalog.py
+++ b/xscen/catalog.py
@@ -302,7 +302,7 @@ def search(self, **columns):
             )
         return cat
 
-    def drop_duplicates(self, columns: list[str] = None):
+    def drop_duplicates(self, columns: Optional[list[str]] = None):
         """Drop duplicates in the catalog based on a subset of columns.
 
         Parameters