class_docstr: Extends QComboBox to add extra functionality.
  
  * Handles dict mappings -- user selects a text key, and the ComboBox indicates
    the selected value.
  * Requires item strings to be unique
  * Remembers selected value if list is cleared and subsequently repopulated
  * setItems() replaces the items in the ComboBox and blocks signals if the
    value ultimately does not change.
class_docstr_tok: ["Extends","QComboBox","to","add","extra","functionality",".","*","Handles","dict","mappings","--","user","selects","a","text","key",",","and","the","ComboBox","indicates","the","selected","value",".","*","Requires","item","strings","to","be","unique","*","Remembers","selected","value","if","list","is","cleared","and","subsequently","repopulated","*","setItems","(",")","replaces","the","items","in","the","ComboBox","and","blocks","signals","if","the","value","ultimately","does","not","change","."]
code: def addItem(self, *args, **kwds):
      # Need to handle two different function signatures for QComboBox.addItem
      try:
          if isinstance(args[0], str):
              text = args[0]
              if len(args) == 2:
                  value = args[1]
              else:
                  value = kwds.get("value", text)
          else:
              text = args[1]
              if len(args) == 3:
                  value = args[2]
              else:
                  value = kwds.get("value", text)
  
      except IndexError:
          raise TypeError(
              "First or second argument of addItem must be a string."
          )
  
      if text in self._items:
          raise Exception(
              'ComboBox already has item named "%s".' % text
          )
  
      self._items[text] = value
      QtWidgets.QComboBox.addItem(self, *args)
      self.itemsChanged()
  
imports: import sys
  from collections import OrderedDict
  from ..Qt import QtWidgets
label_desc: Use image node_id 15 for calling the ComboBox obj's underlying member method code with example usage: obj.addItem() without return types