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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 _keywords_only(f):
 """ Decorate a function so all its arguments must be passed by keyword. A useful utility for decorators that take arguments so that they don't accidentally get passed the thing they're decorating as their first argument. Only works for methods right now. """

    @wraps(f)
    def g(self, **kw):
        return f(self, **kw)
    return g