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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 get_or(self, cache_key, callback, *args, **kwargs):
 """ Get or set the cache using callback and arguments :param cache_key: Cache key for given resource :param callback: Callback if object does not exist :param args: Ordered Argument for the callback :param kwargs: Keyword argument for the callback :return: Output of the callback """

        cached = self.cache.get(cache_key)
        if cached is not None:
            return cached
        else:
            try:
                output = callback(*args, **kwargs)
            except MyCapytain.errors.UnknownCollection as E:
                raise UnknownCollection(str(E))
            except Exception as E:
                raise E
            self.cache.set(cache_key, output, self.TIMEOUT)
            return output