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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 _swap_curly(string):
 """Swap single and double curly brackets"""

    return (
        string.replace('{{ ', '{{').replace('{{', '\x00').replace('{', '{{')
        .replace('\x00', '{').replace(' }}', '}}').replace('}}', '\x00')
        .replace('}', '}}').replace('\x00', '}')
    )