code: def paintEvent(self, evt):
      painter = QtGui.QPainter(self)
      self.paintColorMap(painter, self.contentsRect())
      painter.end()
  
imports: import importlib.util
  import re
  import numpy
  from ..None import colormap
  from ..None import functions
  from ..graphicsItems.GradientPresets import Gradients
  from ..Qt import QtCore, QtGui, QtWidgets
label_desc: Use image node_id 3 for calling the ColorMapButton obj's underlying member method code with example usage: obj.paintEvent(evt) without return types