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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 filtered(self, allowed):
 """ Return a new Options object that is filtered by the specified list of keys. Mutating self.kwargs to filter is unsafe due to the option expansion that occurs on initialization. """

        kws = {k:v for k,v in self.kwargs.items() if k in allowed}
        return self.__class__(key=self.key,
                              allowed_keywords=self.allowed_keywords,
                              merge_keywords=self.merge_keywords, **kws)