def IRAF_image_type(image_type):
    """
    Convert MaximDL default image type names to IRAF

    Parameters
    ----------
    image_type : str
        Value of the FITS header keyword IMAGETYP; acceptable values are
        below in Notes.

    Returns
    -------
    str
        IRAF image type (one of 'BIAS', 'DARK', 'FLAT' or 'LIGHT')

    Notes
    -----
    The MaximDL default is, e.g. 'Bias Frame', which IRAF calls
    'BIAS'. Can safely be called with an IRAF-style image_type.
    """
    return image_type.split()[0].upper()