diff --git a/core/dbt/graph/selector.py b/core/dbt/graph/selector.py
index 53e0589d3af..fdf8adedcfe 100644
--- a/core/dbt/graph/selector.py
+++ b/core/dbt/graph/selector.py
@@ -392,7 +392,7 @@ def get_nodes_from_multiple_specs(
             self,
             graph,
             specs,
-            nodes: Set[str] = None,
+            nodes=None,
             check_existence=False,
             exclude=False
     ):