diff --git a/Src/IronPython/Compiler/Ast/Comprehension.cs b/Src/IronPython/Compiler/Ast/Comprehension.cs
index 81948fd44..42fbc20bd 100644
--- a/Src/IronPython/Compiler/Ast/Comprehension.cs
+++ b/Src/IronPython/Compiler/Ast/Comprehension.cs
@@ -246,7 +246,7 @@ internal override bool ExposesLocalVariable(PythonVariable variable) {
         }
 
         internal override MSAst.Expression/*!*/ GetParentClosureTuple() {
-            Debug.Assert(NeedsLocalContext);
+            Debug.Assert(NeedsLocalContext || IsClosure);
             return MSAst.Expression.Call(null, typeof(PythonOps).GetMethod(nameof(PythonOps.GetClosureTupleFromContext)), Parent.LocalContext);
         }