parameters: (self, event)
docstring: Respond to the "Undo" menu command.
docstring_summary: Respond to the "Undo" menu command.
docstring_tokens: Respond to the Undo menu command .
function: def doUndo(self, event):
          """ Respond to the "Undo" menu command.
          """
          if not self.undoStack: return 
  
          state = self._buildStoredState()
          self.redoStack.append(state)
          state = self.undoStack.pop()
          self._restoreStoredState(state)
function_tokens: def doUndo ( self , event ) : if not self . undoStack : return state = self . _buildStoredState ( ) self . redoStack . append ( state ) state = self . undoStack . pop ( ) self . _restoreStoredState ( state )