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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 do_authorization(self, transactionid, amt):
 """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`) """

        args = self._sanitize_locals(locals())
        return self._call('DoAuthorization', **args)