def copy_keywords(srchdr, dsthdr, keys):
    """Copy a list of FITS keywords from one header to another.

    Parameters
    ----------
    srchdr : `astropy.io.fits.Header`
        Source header
    dsthdr : `astropy.io.fits.Header`
        Destination header
    keys : list
        List of keys

    """
    for key in keys:
        if key in srchdr:
            dsthdr[key] = srchdr[key], srchdr.comments[key]
