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

    i = widget.findText(value)
    if i == -1:
        raise ValueError("%s not found in combo box" % value)
    else:
        return i