qml gui: fix flake8 "F821 undefined name" errors

electrum/gui/qml/qedaemon.py

@@ -215,4 +215,4 @@ class QEDaemon(AuthMixin, QObject):
     def set_password(self, password):
         assert self._use_single_password
         self._logger.debug('about to set password to %s for ALL wallets' % password)
-        update_password_for_directory(self.daemon.config, self._password, password)
+        self.daemon.update_password_for_directory(old_password=self._password, new_password=password)

electrum/gui/qml/qewallet.py

@@ -17,6 +17,7 @@ from electrum.transaction import PartialTxOutput
 from electrum.invoices import (Invoice, InvoiceError,
                                PR_DEFAULT_EXPIRATION_WHEN_CREATING, PR_PAID,
                                PR_UNPAID, PR_UNKNOWN, PR_EXPIRED, PR_UNCONFIRMED)
+from electrum.network import TxBroadcastError, BestEffortRequestFailed
 
 from .qeinvoicelistmodel import QEInvoiceListModel, QERequestListModel
 from .qetransactionlistmodel import QETransactionListModel