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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 refresh_token(self, refresh_token):
 """ Get a new token, using the provided refresh token. Returns the new access_token. """


        response = requests.post('%saccess_token' % OAUTH_URL, {
                                 'refresh_token': refresh_token,
                                 'grant_type': 'refresh_token',
                                 'client_id': self.client_id,
                                 'client_secret': self.client_secret
                                 })
        resp = json.loads(response.content)

        if 'access_token' in resp:
            self.token = resp['access_token']

        return resp