diff --git a/cli/process.py b/cli/process.py
index 4c5fa7f90..3852c3287 100644
--- a/cli/process.py
+++ b/cli/process.py
@@ -21,7 +21,7 @@ all_images_by_type = {}
 
 
 class Result():
-    def __init__(self, typ: str, fn: str, tag: str | None = None, requested: list = None):
+    def __init__(self, typ: str, fn: str, tag: str | None = None, requested: list | None = None):
         self.type = typ
         self.input = fn
         self.output = ''