diff --git a/atst/domain/legacy_task_orders.py b/atst/domain/legacy_task_orders.py
index 86f75b54..e7a5c44f 100644
--- a/atst/domain/legacy_task_orders.py
+++ b/atst/domain/legacy_task_orders.py
@@ -54,9 +54,7 @@ class LegacyTaskOrders(object):
 
     @classmethod
     def update(cls, legacy_task_order, dct):
-        updated = update_obj(
-            legacy_task_order, dct, ignore_vals=lambda v: v in ["", None]
-        )
+        updated = update_obj(legacy_task_order, dct, ignore_vals=["", None])
         db.session.add(updated)
         db.session.commit()
         return updated
diff --git a/atst/utils/__init__.py b/atst/utils/__init__.py
index 195484c9..5852ebf4 100644
--- a/atst/utils/__init__.py
+++ b/atst/utils/__init__.py
@@ -33,9 +33,9 @@ def getattr_path(obj, path, default=None):
     return _obj
 
 
-def update_obj(obj, dct, ignore_vals=lambda v: v is None):
+def update_obj(obj, dct, ignore_vals=[None]):
     for k, v in dct.items():
-        if hasattr(obj, k) and not ignore_vals(v):
+        if hasattr(obj, k) and v not in ignore_vals:
             setattr(obj, k, v)
     return obj