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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 get_first_language(self, site_id=None):
 """ Return the first language for the current site. This can be used for user interfaces, where the languages are displayed in tabs. """

        if site_id is None:
            site_id = getattr(settings, 'SITE_ID', None)

        try:
            return self[site_id][0]['code']
        except (KeyError, IndexError):
            # No configuration, always fallback to default language.
            # This is essentially a non-multilingual configuration.
            return self['default']['code']