# We can now use RBF, but the feerate must be higher than that of the first transaction.
        with pytest.raises(RpcError, match=f"Feerate 1 too low for minimum feerate 2."):
            lianad.rpc.rbfpsbt(first_txid, False, 1)
        # Using a higher feerate works.
        lianad.rpc.rbfpsbt(first_txid, False, 2)
        # Let's use an even higher feerate.
        rbf_1_res = lianad.rpc.rbfpsbt(first_txid, False, 10)
        rbf_1_psbt = PSBT.from_base64(rbf_1_res["psbt"])
    
        # Check the locktime is being set.
        tip_height = bitcoind.rpc.getblockcount()
        locktime = rbf_1_psbt.tx.nLockTime
        assert tip_height - 100 <= locktime <= tip_height
    
        # The inputs are the same in both (no new inputs needed in the replacement).
        assert sorted(i.prevout.serialize() for i in first_psbt.tx.vin) == sorted(
            i.prevout.serialize() for i in rbf_1_psbt.tx.vin
        )
        # Check non-change output is the same in both.
        assert first_psbt.tx.vout[0].nValue == rbf_1_psbt.tx.vout[0].nValue
        assert first_psbt.tx.vout[0].scriptPubKey == rbf_1_psbt.tx.vout[0].scriptPubKey
        # Change address is the same but change amount will be lower in the replacement to pay higher fee.
        assert first_psbt.tx.vout[1].nValue > rbf_1_psbt.tx.vout[1].nValue
        assert first_psbt.tx.vout[1].scriptPubKey == rbf_1_psbt.tx.vout[1].scriptPubKey
        # Broadcast the replacement and wait for it to be detected.
        rbf_1_txid = sign_and_broadcast_psbt(lianad, rbf_1_psbt)
        wait_for(
            lambda: all(
                c["spend_info"] is not None and c["spend_info"]["txid"] == rbf_1_txid
                for c in lianad.rpc.listcoins([], first_outpoints)["coins"]
            )
        )
        mempool_rbf_1 = bitcoind.rpc.getmempoolentry(rbf_1_txid)
        # Note that in the mempool entry, "ancestor" includes rbf_1_txid itself.
        rbf_1_feerate = (
            mempool_rbf_1["fees"]["ancestor"] * COIN / mempool_rbf_1["ancestorsize"]
        )
        assert 9.75 < rbf_1_feerate < 10.25
        # If we try to RBF the first transaction again, it will use the first RBF's
        # feerate to set the min feerate, instead of 1 sat/vb of first
        # transaction:
>       with pytest.raises(
            RpcError, match=f"Feerate {int(rbf_1_feerate)} too low for minimum feerate 10."
        ):
E       AssertionError: Regex pattern did not match.
E        Regex: 'Feerate 10 too low for minimum feerate 10.'
E        Input: 'RPC call failed: method: rbfpsbt, params: (\'9dce39c139c312aab431780aa55f521f3d0dcc5e1785befd766ad224c10e95f0\', False, 10), error: {\'code\': -32602, \'message\': "RBF error: \'Feerate 10 too low for minimum feerate 11.\'."}'

tests/test_rpc.py:1147: AssertionError
--------------------------- Captured stdout teardown ---------------------------
Test failed, leaving directory '/tmp/lianad-tests-rsin8isk/test_rbfpsbt_bump_fee_1' intact
=========================== short test summary info ============================
FAILED tests/test_rpc.py::test_rbfpsbt_bump_fee - AssertionError: Regex pattern did not match.
 Regex: 'Feerate 10 too low for minimum feerate 10.'
 Input: 'RPC call failed: method: rbfpsbt, params: (\'9dce39c139c312aab431780aa55f521f3d0dcc5e1785befd766ad224c10e95f0\', False, 10), error: {\'code\': -32602, \'message\': "RBF error: \'Feerate 10 too low for minimum feerate 11.\'."}'
=================== 1 failed, 15 passed in 146.75s (0:02:26) ===================