def METHOD_NAME(self):
    """
    Given a language only and the system only has values that with regions specified, then 
    the system should pick the first preflabel with the same language code 
    """
    concept = Concept()
    concept.values = [
        ConceptValue({"type": "prefLabel", "category": "label", "value": "test pref label en-US", "language": "en-US"}),
        ConceptValue({"type": "prefLabel", "category": "label", "value": "test pref label es", "language": "es-SP"}),
        ConceptValue({"type": "altLabel", "category": "label", "value": "test alt label en-US", "language": "en-US"}),
    ]
    self.assertEqual(concept.get_preflabel(lang="en").value, "test pref label en-US")