Make keys parameter requiring func parameter in _addButton explicit

qt/aqt/editor.py

@@ -252,6 +252,7 @@ class Editor:
         """Assign func to bridge cmd, register shortcut, return button"""
         if func:
             self._links[cmd] = func
+
             if keys:
 
                 def on_activated():
@@ -273,6 +274,7 @@ class Editor:
                     self.widget,
                     activated=on_hotkey,
                 )
+
         btn = self._addButton(
             icon,
             cmd,