[{'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: In addition to this, Wooga may collect and use a user's personal data if it is needed for billing any games and services that have been used. Wooga may also use the data in locked form to comply with retention periods laid down by law or required by contract."}, {'role': 'assistant', 'content': 'This clause is fair. The privacy practices mentioned are: nan.'}]