code: def colorMapChanged(self):
      cmap = self.colorMap()
      self.sigColorMapChanged.emit(cmap)
      self.update()
  
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 2 for calling the ColorMapButton obj's underlying member method code with example usage: obj.colorMapChanged() without return types