[{'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: (b) You should therefore always consult the respective privacy policies of these third-party ad servers or ad networks for more information on their practices and for instructions on how to opt-out of certain practices."}, {'role': 'assistant', 'content': 'This clause is fair. The privacy practices mentioned are: nan.'}]