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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 _compute_mjd(self, kw, val):
 """ Sometimes that MJD-OBS-CENTER keyword maps to a three component string, instead of a single value. @param kw: a list of keywords @param val: a list of matching values @return: the MJD-OBS-CENTER as a julian date. """

        try:
            idx = kw.index('MJD-OBS-CENTER')
        except ValueError:
            return
        if len(val) == len(kw):
            return
        if len(val) - 2 != len(kw):
            raise ValueError("convert: keyword/value lengths don't match: {}/{}".format(kw, val))
        val.insert(idx, Time("{} {} {}".format(val.pop(idx), val.pop(idx), val.pop(idx)),
                             format='mpc',
                             scale='utc').mjd)
        logging.debug("Computed MJD: {}".format(val[idx]))