[{'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: 18. Changes to this Privacy Policy Comcast reserves the right to change this Privacy Policy from time to time. When we do change it, we will make a copy of the updated Privacy Policy available to you before it takes effect. If we make material changes to this Privacy Policy, we will also notify you by email, direct mail, or other reasonable methods that we select. If we make material changes to this Privacy Policy, we will give you the opportunity to opt-out for information that we have collected before, or may collect after, a new Privacy Policy containing material changes takes effect."}, {'role': 'assistant', 'content': 'This clause is fair. The privacy practices mentioned are: nan.'}]