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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 master_key_required(func):
    '''decorator describing methods that require the master key'''
    def ret(obj, *args, **kw):
        conn = ACCESS_KEYS
        if not (conn and conn.get('master_key')):
            message = '%s requires the master key' % func.__name__
            raise core.ParseError(message)
        func(obj, *args, **kw)
    return ret