How to use the pyhindsight.browsers.chrome.CacheEntry function in pyhindsight

return item

        if isinstance(obj, Chrome.PreferenceItem):
            item = HindsightEncoder.base_encoder(obj)

            item['timestamp_desc'] = 'Update Time'
            item['data_type'] = 'chrome:preferences:entry'
            item['source_long'] = 'Chrome Preferences'

            item['message'] = u'Updated preference: {}: {})'.format(
                item['key'], item['value'])

            del(item['row_type'], item['name'])
            return item

        if isinstance(obj, CacheEntry):
            item = HindsightEncoder.base_encoder(obj)

            item['timestamp_desc'] = 'Last Visit Time'
            item['data_type'] = 'chrome:cache:entry'
            item['source_long'] = 'Chrome Cache'
            item['original_url'] = item['url']
            item['cache_type'] = item['row_type']
            item['cached_state'] = item['name']

            item['message'] = u'Original URL: {}'.format(
                item['original_url'])

            del(item['row_type'], item['name'], item['timezone'])
            return item