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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def addChanged(self):
 """Called when "add new" combo is changed The parameter MUST have an 'addNew' method defined. """

        if self.addWidget.currentIndex() == 0:
            return
        typ = asUnicode(self.addWidget.currentText())
        self.param.addNew(typ)
        self.addWidget.setCurrentIndex(0)