def deleteDistortionKeywords(hdr):
    """ Delete distortion related keywords from output drizzle science header
        since the drizzled image should have no remaining distortion.
    """
    dist_kws = ['D2IMERR1', 'D2IMERR2', 'D2IMDIS1', 'D2IMDIS2', 'D2IM1.*',
        'D2IM2.*', 'D2IMEXT']
    for kw in dist_kws:
        try:
            del hdr[kw]
        except KeyError as e:
            pass
