code: def close(self):
      self.plotItem.close()
      self.plotItem = None
      # self.scene().clear()
      # self.mPlotItem.close()
      self.setParent(None)
      super(PlotWidget, self).close()
  
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 2 for calling the PlotWidget obj's underlying member method code with example usage: obj.close() without return types