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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 authorize(self, consumer_key, consumer_secret, callback_url=None, access_token=None, access_token_secret=None):
 """ Call this with your consumer key, secret and callback URL, to generate a token for verification. """

        self.consumer_key = consumer_key
        self.consumer_secret = consumer_secret

        if not access_token and not access_token_secret:
            if not callback_url:
                return (False, "Callback URL required")
            oauth = OAuth1(
                consumer_key,
                client_secret=consumer_secret,
                callback_uri=callback_url)
            r = requests.post(self.url('REQUEST_TOKEN'), auth=oauth)
            if r.status_code == 200:
                creds = parse_qs(r.content)

                self.access_token = creds.get('oauth_token')[0]
                self.access_token_secret = creds.get('oauth_token_secret')[0]
            else:
                return (False, r.content)
        else:
            self.finalize_oauth(access_token, access_token_secret)

        return (True, None)