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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 keyword_only(func):
 """ A decorator that forces keyword arguments in the wrapped method and saves actual input keyword arguments in `_input_kwargs`. .. note:: Should only be used to wrap a method where first arg is `self` """

    @wraps(func)
    def wrapper(self, *args, **kwargs):
        if len(args) > 0:
            raise TypeError("Method %s forces keyword arguments." % func.__name__)
        self._input_kwargs = kwargs
        return func(self, **kwargs)
    return wrapper