[{'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: If a user has signed up to Facebook but does not want Facebook to collect data via Wooga's website and link it up with the data stored on Facebook, it must log off Facebook before visiting Wooga ."}, {'role': 'assistant', 'content': 'This clause is fair. The privacy practices mentioned are: nan.'}]