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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_channel_definition(self, jp2h, colr):
 """Validate the channel definition box."""

        cdef_lst = [j for (j, box) in enumerate(jp2h.box)
                    if box.box_id == 'cdef']
        if len(cdef_lst) > 1:
            msg = ("Only one channel definition box is allowed in the "
                   "JP2 header.")
            raise IOError(msg)
        elif len(cdef_lst) == 1:
            cdef = jp2h.box[cdef_lst[0]]
            if colr.colorspace == core.SRGB:
                if any([chan + 1 not in cdef.association or
                        cdef.channel_type[chan] != 0 for chan in [0, 1, 2]]):
                    msg = ("All color channels must be defined in the "
                           "channel definition box.")
                    raise IOError(msg)
            elif colr.colorspace == core.GREYSCALE:
                if 0 not in cdef.channel_type:
                    msg = ("All color channels must be defined in the "
                           "channel definition box.")
                    raise IOError(msg)