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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 requires_libsodium(func):
 """ Mark a function as requiring libsodium. If no libsodium support is detected, a `RuntimeError` is thrown. """

    @wraps(func)
    def wrapper(*args, **kwargs):
        libsodium_check()
        return func(*args, **kwargs)

    return wrapper