code: def widgetGroupInterface(self):
      return (None, PlotWidget.saveState, PlotWidget.restoreState)
  
file_path: pyqtgraph/pyqtgraph/widgets/PlotWidget.py
imports: from ..graphicsItems.PlotItem import PlotItem
  from ..Qt import QtCore, QtWidgets
  from .GraphicsView import GraphicsView
label_desc: Use image node_id 5 for calling the PlotWidget obj's underlying member method code with example usage: obj.widgetGroupInterface() and returns: None,  PlotWidget,  PlotWidget