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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 _create_database(self):
 """ Set up database Creates tables required for the authentication module. """


        self._logger.info('creating user database')
        sql = '''CREATE TABLE IF NOT EXISTS user (
            username NOT NULL PRIMARY KEY,
            pwd_salt NOT NULL,
            pwd_hash NOT NULL,
            full_name,
            trusted NOT NULL DEFAULT 0,
            readonly NOT NULL DEFAULT 0
        )'''
        self._db_curs.execute(sql)
        self._db_conn.commit()