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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 require_root(fn):
 """ Decorator to make sure, that user is root. """

    @wraps(fn)
    def xex(*args, **kwargs):
        assert os.geteuid() == 0, \
            "You have to be root to run function '%s'." % fn.__name__
        return fn(*args, **kwargs)

    return xex