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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 _find_combo_data(widget, value):
 """ Returns the index in a combo box where itemData == value Raises a ValueError if data is not found """

    # Here we check that the result is True, because some classes may overload
    # == and return other kinds of objects whether true or false.
    for idx in range(widget.count()):
        if widget.itemData(idx) is value or (widget.itemData(idx) == value) is True:
            return idx
    else:
        raise ValueError("%s not found in combo box" % (value,))