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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 _validate_jp2_colr(self, boxes):
 """ Validate JP2 requirements on colour specification boxes. """

        lst = [box for box in boxes if box.box_id == 'jp2h']
        jp2h = lst[0]
        for colr in [box for box in jp2h.box if box.box_id == 'colr']:
            if colr.approximation != 0:
                msg = ("A JP2 colr box cannot have a non-zero approximation "
                       "field.")
                raise IOError(msg)