not set, fall back to wallet fee estimation) 
                               Specify a fee rate in sat/vB instead of relying on the built-in fee estimator.
                               Must be at least 1.000 sat/vB higher than the current transaction fee rate.
                               WARNING: before version 0.21, fee_rate was in BTC/kvB. As of 0.21, fee_rate is in sat/vB.
                               
replaceable                    (boolean, optional, default=true) Whether the new transaction sho