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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 authenticated_handler(self, f):
 """Decorates the authentication callback endpoint. The endpoint should take one argument, a flask.ext.micropub.AuthResponse. """

        @functools.wraps(f)
        def decorated():
            resp = self._handle_authenticate_response()
            return f(resp)
        self._authenticated_handler = decorated
        return decorated