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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 component(self, **kwargs):
 """ Return a key that specifies data the sub-selection """

        kwargs_copy = self.base_dict.copy()
        kwargs_copy.update(**kwargs)
        self._replace_none(kwargs_copy)        
        try:
            return NameFactory.component_format.format(**kwargs_copy)
        except KeyError:
            return None