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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 tag_timexes(self):
 """Create ``timexes`` layer. Depends on morphological analysis data in ``words`` layer and tags it automatically, if it is not present."""

        if not self.is_tagged(ANALYSIS):
            self.tag_analysis()
        if not self.is_tagged(TIMEXES):
            if self.__timex_tagger is None:
                self.__timex_tagger = load_default_timex_tagger()
            self.__timex_tagger.tag_document(self, **self.__kwargs)
        return self