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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 __cache(self, file, content, document):
 """ Caches given file. :param file: File to cache. :type file: unicode :param content: File content. :type content: list :param document: File document. :type document: QTextDocument """


        self.__files_cache.add_content(**{file: CacheData(content=content, document=document)})