def METHOD_NAME(self):
    """Assert that a valid language code is found correctly."""
    self.assertEqual(select2_widget.get_i18n_name('en'), 'en')
    self.assertEqual(select2_widget.get_i18n_name('en-US'), 'en')
    self.assertEqual(select2_widget.get_i18n_name('fr-US'), 'fr')
    self.assertEqual(select2_widget.get_i18n_name('fr-FR'), 'fr')
    self.assertEqual(select2_widget.get_i18n_name('sr-Cyrl'), 'sr-Cyrl')
    self.assertEqual(select2_widget.get_i18n_name('zh-TW'), 'zh-TW')
    self.assertEqual(select2_widget.get_i18n_name('zh-Hant'), 'zh-TW')