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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def buildSkyCatalog(self):
 """ Convert sky catalog for all chips into a single catalog for the entire field-of-view of this image. """

        self.all_radec = None
        self.all_radec_orig = None
        ralist = []
        declist = []
        fluxlist = []
        idlist = []
        for scichip in self.chip_catalogs:
            skycat = self.chip_catalogs[scichip]['catalog'].radec
            xycat = self.chip_catalogs[scichip]['catalog'].xypos
            if skycat is not None:
                ralist.append(skycat[0])
                declist.append(skycat[1])
                if xycat is not None and len(xycat) > 2:
                    fluxlist.append(xycat[2])
                    idlist.append(xycat[3])
                elif len(skycat) > 2:
                    fluxlist.append(skycat[2])
                    idlist.append(skycat[3])
                else:
                    fluxlist.append([999.0]*len(skycat[0]))
                    idlist.append(np.arange(len(skycat[0])))

                self.all_radec = [np.concatenate(ralist),np.concatenate(declist),
                        np.concatenate(fluxlist),np.concatenate(idlist)]
                self.all_radec_orig = copy.deepcopy(self.all_radec)