def race_iter_h(r):
    """Return a census race iteration code for a PUMS records, for just
    the Non-hispanic White / Hispanic distinction"""
    is_hisp = r.HISP != 1

    if r.RAC1P == 1 and not is_hisp:
        return 'h'  # non hispanic white
    elif is_hisp:
        return 'i'
    else:
        return None