docs: 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