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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_social_friend_ids(self, social_auth_user):
 """ fetches the user's social friends from its provider user is an instance of UserSocialAuth returns collection of ids this method can be used asynchronously as a background process (celery) """


        # Type check
        self.assert_user_is_social_auth_user(social_auth_user)

        # Get friend finder backend
        friends_provider = SocialFriendsFinderBackendFactory.get_backend(social_auth_user.provider)

        # Get friend ids
        friend_ids = friends_provider.fetch_friend_ids(social_auth_user)

        return friend_ids