Method fee

code-ch13/tx.py:201–212

Returns the fee of this transaction in satoshi

(self)

    # end::source4[]

    def fee(self):
        '''Returns the fee of this transaction in satoshi'''
        # initialize input sum and output sum
        input_sum, output_sum = 0, 0
        # use TxIn.value() to sum up the input amounts
        for tx_in in self.tx_ins:
            input_sum += tx_in.value(self.testnet)
        # use TxOut.amount to sum up the output amounts
        for tx_out in self.tx_outs:
            output_sum += tx_out.amount
        # fee is input sum - output sum
        return input_sum - output_sum

    def sig_hash(self, input_index, redeem_script=None):
        '''Returns the integer representation of the hash that needs to get