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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fetch_friend_ids(self, user):
 """ fethces friend id's from twitter Return: collection of friend ids """

        friends = self.fetch_friends(user)
        friend_ids = []
        for friend in friends:
            friend_ids.append(friend.id)
        return friend_ids