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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def iter_languages(self):
 """Iterate over list of languages."""

        default_lang = self.babel.default_locale.language
        default_title = self.babel.default_locale.get_display_name(
            default_lang)

        yield (default_lang, default_title)

        for l, title in current_app.config.get('I18N_LANGUAGES', []):
            yield l, title