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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 _save(self):
 """Save the attributes defined on _pickle_attributes in a pickle file. This improves a lot the nth run as the log file does not need to be processed every time. """

        with open(self._pickle_file, 'wb') as source:
            pickler = pickle.Pickler(source, pickle.HIGHEST_PROTOCOL)

            for attribute in self._pickle_attributes:
                attr = getattr(self, attribute, None)
                pickler.dump(attr)