code: def _save_token_cache(self, new_cache):
          'Write out to the filesystem a cache of the OAuth2 information.'
          logging.debug('Looking to write to local authentication cache...')
          if not self._check_token_cache_type(new_cache):
              logging.error('Attempt to save a bad value: %s', new_cache)
              return
          try:
              logging.debug('About to write to fs cache file: %s',
                            self.token_cache_file)
              with open(self.token_cache_file, 'wb') as f:
                  cPickle.dump(new_cache, f, protocol=cPickle.HIGHEST_PROTOCOL)
                  logging.debug('Finished dumping cache_value to fs cache file.')
          except:
              logging.exception(
                  'Could not successfully cache OAuth2 secrets on the file '
                  'system.'f _save_token_cache(self, new_cache):
          'Write out to the filesystem a cache of the OAuth2 information.'
          logging.debug('Looking to write to local authentication cache...')
          if not self._check_token_cache_type(new_cache):
              logging.error('Attempt to save a bad value: %s', new_cache)
              return
          try:
              logging.debug('About to write to fs cache file: %s',
                            self.token_cache_file)
              with open(self.token_cache_file, 'wb') as f:
                  cPickle.dump(new_cache, f, protocol=cPickle.HIGHEST_PROTOCOL)
                  logging.debug('Finished dumping cache_value to fs cache file.')
          except:
              logging.exception(
                  'Could not successfully cache OAuth2 secrets on the file '
                  'system.')
docs: Write out to the filesystem a cache of the OAuth2 information.