[{'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: MODIFICATIONS Our Privacy Policy may change from time to time. We will post any Privacy Policy changes on this page. We will not make any material retroactive changes to this Privacy Policy, including for changes involving the use of your Personal User Information, without your affirmative consent."}, {'role': 'assistant', 'content': 'This clause is fair. The privacy practices mentioned are: nan.'}]