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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 add(self, widget, *args, **kwargs):
 """Insert new element. Usage: window.add(widget, **{ 'prop1': val, 'prop2': val2 }) """

        ins_widget = widget(*args, **kwargs)
        self.__iadd__(ins_widget)
        return ins_widget