diff --git a/midas/checker/python.py b/midas/checker/python.py
index be3d05f..c149d8d 100644
--- a/midas/checker/python.py
+++ b/midas/checker/python.py
@@ -1233,7 +1233,7 @@ class PythonTyper(
                 node: ast.Expression = ast.parse(value, mode="eval")
                 return parser._parse_type(node.body)
             case p.VariableExpr(name=name):
-                return p.BaseType(location=location, base=name, param=None)
+                return p.BaseType(location=location, base=name, args=())
             case _:
                 raise NotImplementedError
 
diff --git a/tests/serializer/python.py b/tests/serializer/python.py
index 7c29616..4e531cb 100644
--- a/tests/serializer/python.py
+++ b/tests/serializer/python.py
@@ -30,6 +30,7 @@ from midas.ast.python import (
     Stmt,
     SubscriptExpr,
     TernaryExpr,
+    TupleExpr,
     TypeAssign,
     UnaryExpr,
     VariableExpr,