diff --git a/numpydoc/tests/test_validate.py b/numpydoc/tests/test_validate.py
index 0671684b..d41e4bd0 100644
--- a/numpydoc/tests/test_validate.py
+++ b/numpydoc/tests/test_validate.py
@@ -1348,7 +1348,6 @@ def test_bad_generic_functions(self, capsys, func):
         assert isinstance(errors, list)
         assert errors
 
-    @pytest.mark.filterwarnings("ignore::DeprecationWarning")
     @pytest.mark.parametrize(
         "klass,func,msgs",
         [
diff --git a/numpydoc/validate.py b/numpydoc/validate.py
index 7275758b..0f939166 100644
--- a/numpydoc/validate.py
+++ b/numpydoc/validate.py
@@ -521,9 +521,9 @@ def get_returns_not_on_nested_functions(node):
         if tree:
             returns = get_returns_not_on_nested_functions(tree[0])
             return_values = [r.value for r in returns]
-            # Replace NameConstant nodes valued None for None.
+            # Replace Constant nodes valued None for None.
             for i, v in enumerate(return_values):
-                if isinstance(v, ast.NameConstant) and v.value is None:
+                if isinstance(v, ast.Constant) and v.value is None:
                     return_values[i] = None
             return any(return_values)
         else: