How to use the tweakwcs.wcsimage.WCSGroupCatalog function in tweakwcs

object.

        Parameters
        ----------
        wcsim: WCSImageCatalog, WCSGroupCatalog, RefCatalog, SphericalPolygon
            Another object that should be intersected with this
            `WCSImageCatalog`.

        Returns
        -------
        polygon: SphericalPolygon
            A :py:class:`~spherical_geometry.polygon.SphericalPolygon` that is
            the intersection of this `WCSImageCatalog` and `wcsim`.

        """
        if isinstance(wcsim, (WCSImageCatalog, WCSGroupCatalog, RefCatalog)):
            return self._polygon.intersection(wcsim.polygon)
        else:
            return self._polygon.intersection(wcsim)

try:
        # Attempt to set initial status to FAILED.
        tpwcs.meta['fit_info'] = {'status': 'FAILED: Unknown error'}
    except Exception:
        raise AttributeError("Unable to set/modify tpwcs.meta attribute.")

    # check fitgeom:
    fitgeom = fitgeom.lower()
    if fitgeom not in ['shift', 'rscale', 'general']:
        raise ValueError("Unsupported 'fitgeom'. Valid values are: "
                         "'shift', 'rscale', or 'general'")

    wimcat = WCSImageCatalog(imcat, tpwcs,
                             name=imcat.meta.get('name', 'Unnamed'))
    wgcat = WCSGroupCatalog(wimcat, name=imcat.meta.get('name', 'Unnamed'))
    wrefcat = RefCatalog(refcat, name=imcat.meta.get('name', 'Unnamed'))

    succes = wgcat.align_to_ref(refcat=wrefcat, match=None, minobj=None,
                                fitgeom=fitgeom, nclip=nclip, sigma=sigma)

    tpwcs.meta['fit_info'] = wimcat.fit_info
    if not succes:
        log.warning("Failed to align catalog '{}'.".format(wgcat.name))

    # log running time:
    runtime_end = datetime.now()
    log.info(" ")
    log.info("***** {:s}.{:s}() ended on {}"
             .format(__name__, function_name, runtime_end))
    log.info("***** {:s}.{:s}() TOTAL RUN TIME: {}"
             .format(__name__, function_name, runtime_end - runtime_begin))

raise TypeError("Unsupported 'refcat' type. Supported 'refcat' "
                            "types are 'tweakwcs.tpwcs.TPWCS' and "
                            "'astropy.table.Table'")

    # find group ID and assign images to groups:
    grouped_images = collections.defaultdict(list)
    for wcat in wcs_im_cats:
        grouped_images[wcat.group_id].append(wcat)

    # create WCSImageCatalog and WCSGroupCatalog:
    wcs_gcat = []
    for group_id, wcatalogs in grouped_images.items():
        if group_id is None:
            for wcat in wcatalogs:
                wcs_gcat.append(
                    WCSGroupCatalog(wcat, name='GROUP ID: None')
                )

        else:
            gcat = WCSGroupCatalog(
                wcatalogs,
                name='GROUP ID: {}'.format(group_id)
            )
            if not len(gcat.catalog):
                log.warning("Group with ID '{}' will not be aligned: empty "
                            "source catalog".format(group_id))

                for wcat in wcatalogs:
                    wcat.tpwcs.meta['fit_info'] = {
                        'status': 'FAILED: empty source catalog'
                    }

# find group ID and assign images to groups:
    grouped_images = collections.defaultdict(list)
    for wcat in wcs_im_cats:
        grouped_images[wcat.group_id].append(wcat)

    # create WCSImageCatalog and WCSGroupCatalog:
    wcs_gcat = []
    for group_id, wcatalogs in grouped_images.items():
        if group_id is None:
            for wcat in wcatalogs:
                wcs_gcat.append(
                    WCSGroupCatalog(wcat, name='GROUP ID: None')
                )

        else:
            gcat = WCSGroupCatalog(
                wcatalogs,
                name='GROUP ID: {}'.format(group_id)
            )
            if not len(gcat.catalog):
                log.warning("Group with ID '{}' will not be aligned: empty "
                            "source catalog".format(group_id))

                for wcat in wcatalogs:
                    wcat.tpwcs.meta['fit_info'] = {
                        'status': 'FAILED: empty source catalog'
                    }

                continue

            wcs_gcat.append(gcat)