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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_missing_languages(self, field_name, db_table):
 """ Gets only missings fields. """

        db_table_fields = self.get_table_fields(db_table)
        for lang_code in AVAILABLE_LANGUAGES:
            if build_localized_fieldname(field_name, lang_code) not in db_table_fields:
                yield lang_code