Add exception for watch-only wallets trying to perform a spend op

monero/backends/jsonrpc.py

@@ -420,6 +420,7 @@ _err2exc = {
     -16: exceptions.TransactionNotPossible,
     -17: exceptions.NotEnoughMoney,
     -20: exceptions.AmountIsZero,
+    -29: exceptions.WalletIsWatchOnly,
     -37: exceptions.NotEnoughUnlockedMoney,
     -38: exceptions.NoDaemonConnection,
     -43: exceptions.WalletIsNotDeterministic, # https://github.com/monero-project/monero/pull/4653

monero/exceptions.py

@@ -50,3 +50,6 @@ class AccountIndexOutOfBound(AccountException):
 
 class AddressIndexOutOfBound(AccountException):
     pass
+
+class WalletIsWatchOnly(MoneroException):
+    pass