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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):
 """ fetches friend email's from g+ Return: collection of friend emails (ids) """

        friends = self.fetch_friends(user)

        return [friend['ns1_email']['address']
                for friend in friends
                if 'ns1_email' in friend]