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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 extend(self):
 """Extend the OAuth token."""

        graph = GraphAPI()

        response = graph.get('oauth/access_token',
            client_id = FACEBOOK_APPLICATION_ID,
            client_secret = FACEBOOK_APPLICATION_SECRET_KEY,
            grant_type = 'fb_exchange_token',
            fb_exchange_token = self.token
        )

        components = parse_qs(response)

        self.token = components['access_token'][0]
        self.expires_at = now() + timedelta(seconds = int(components['expires'][0]))

        self.save()