gh-39509: Add a doctest for HomsetsCategory._make_named_class_key
    
Follow-up to #39160 .



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preview. (no visible change, method is private.)

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URL: #39509
Reported by: user202729
Reviewer(s):

Author: Release Manager

src/sage/categories/homsets.py

@@ -163,6 +163,11 @@ def _make_named_class_key(self, name):
 
             - :meth:`CategoryWithParameters`
             - :meth:`CategoryWithParameters._make_named_class_key`
+
+        TESTS::
+
+            sage: ModulesWithBasis(ZZ).Homsets()._make_named_class_key('parent_class')
+            <class 'sage.categories.modules_with_basis.ModulesWithBasis.parent_class'>
         """
         return getattr(self.base_category(), name)