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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 authorized(self, request_token):
 """Create a verifier for an user authorized client"""

        verifier = generate_token(length=self.verifier_length[1])
        self.save_verifier(request_token, verifier)
        response = [
            (u'oauth_token', request_token),
            (u'oauth_verifier', verifier)
        ]
        callback = self.get_callback(request_token)
        return redirect(add_params_to_uri(callback, response))