[{'role': 'user', 'content': "Analyze the following clause from a privacy policy and determine if it's fair or unfair. Also identify any privacy practices mentioned: On receiving such a request, Waze will use reasonable efforts to delete such information, however please note we may not delete information immediately from our back-up systems."}, {'role': 'assistant', 'content': 'This clause is fair. The privacy practices mentioned are: nan.'}]