class_docstr: This class provides a widget allowing the user to customize color mapping
  for multi-column data. Given a list of field names, the user may specify
  multiple criteria for assigning colors to each record in a numpy record array.
  Multiple criteria are evaluated and combined into a single color for each
  record by user-defined compositing methods.
  
  For simpler color mapping using a single gradient editor, see 
  :class:`GradientWidget <pyqtgraph.GradientWidget>`
code: def saveState(self):
      return self.params.saveState()
  
imports: from collections import OrderedDict
  import numpy
  from ..None import functions
  from ..None import parametertree
  from ..Qt import QtCore
label_desc: Use image node_id 4 for calling the ColorMapWidget obj's underlying member method code with example usage: obj.saveState() and returns: self