code: def do_authorization(self, transactionid, amt):
          
          args = self._sanitize_locals(locals())
          return self._call('DoAuthorization', **args)
docs: Shortcut for the DoAuthorization method.
  
          Use the TRANSACTIONID from DoExpressCheckoutPayment for the
          ``transactionid``. The latest version of the API does not support the
          creation of an Order from `DoDirectPayment`.
  
          The `amt` should be the same as passed to `DoExpressCheckoutPayment`.
  
          Flow for a payment involving a `DoAuthorization` call::
  
               1. One or many calls to `SetExpressCheckout` with pertinent order
                  details, returns `TOKEN`
               1. `DoExpressCheckoutPayment` with `TOKEN`, `PAYMENTACTION` set to
                  Order, `AMT` set to the amount of the transaction, returns
                  `TRANSACTIONID`
               1. `DoAuthorization` with `TRANSACTIONID` and `AMT` set to the
                  amount of the transaction.
               1. `DoCapture` with the `AUTHORIZATIONID` (the `TRANSACTIONID`
                  returned by `DoAuthorization`)