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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 _log_prefix(self, prefix, request):
 """ Returns a formatted prefix for logging for the given request. """

        # After a celery task runs, the request cache is cleared. So if celery
        # tasks are running synchronously (CELERY_ALWAYS _EAGER), "guid_key"
        # will no longer be in the request cache when process_response executes.
        cached_guid_response = self._cache.get_cached_response(self.guid_key)
        cached_guid = cached_guid_response.get_value_or_default(u"without_guid")
        return u"{} request '{} {} {}'".format(prefix, request.method, request.path, cached_guid)