def authorize_from_refresh_token(refresh_token)
      @access_token = oauth_client.get_token({
        client_id:     oauth_client.id,
        client_secret: oauth_client.secret,
        refresh_token: refresh_token,
        grant_type:    'refresh_token'
      })
    end
def authorize_from_refresh_token(refresh_token)
      @access_token = oauth_client.get_token({
        client_id:     oauth_client.id,
        client_secret: oauth_client.secret,
        refresh_token: refresh_token,
        grant_type:    'refresh_token'
      })
    end
Authorize client by fetching a new access_token via refresh token

 @example
   client.authorize_from_refresh_token("DEF")

 @param [String] refresh_token

 @return [OAuth2::AccessToken]

 @api public