qt main_window: add get_password utility function

electrum/gui/qt/main_window.py

@@ -1990,6 +1990,11 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger, QtEventListener):
         else:
             self.show_error(_("Wallet file not found: {}").format(basename))
 
+    @protected
+    def get_password(self, password):
+        # may be used by plugins to get password
+        return password
+
     @protected
     def show_seed_dialog(self, password):
         if not self.wallet.has_seed():