How to use the pkgbuilder.PBError function in pkgbuilder

def download(self, urlpath, filename, prot='http'):
        """Downloads an AUR tarball (http) to the current directory.

:Arguments: URL, filename for saving, protocol.
:Input: none.
:Output: none.
:Returns: bytes downloaded.
:Exceptions:
    PBError, IOError, requests.exceptions.*
:Message codes: ERR3101, ERR3102."""
        r = requests.get(self.aururl.format(prot, urlpath))

        # Error handling.
        if r.status_code != 200:
            raise PBError(_('[ERR3102] download: HTTP Error {0}').format(
                r.status_code))
        elif r.headers['content-length'] == '0':
            raise PBError(_('[ERR3101] download: 0 bytes downloaded'))

        f = open(filename, 'wb')
        f.write(r.content)
        f.close()
        return r.headers['content-length']

DS.protocol = args.protocol
    try:
        utils = Utils()
        build = Build()
        DS.log.info('Arguments parsed.')

        if not args.color:
            # That's awesome in variables AND 2.x series.
            # …and it was moved to PBDS.
            DS.colorsoff()

        if args.info:
            for pkgname in args.pkgs:
                pkg = utils.info(pkgname)
                if pkg is None:
                    raise PBError(_('Package {0} not found.').format(
                        pkgname))
                # TRANSLATORS: space it properly.  `yes/no' below are
                # for `out of date'.
                print(_("""Category       : {cat}
Name           : {nme}
Version        : {ver}
URL            : {url}
Licenses       : {lic}
Votes          : {cmv}
Out of Date    : {ood}
Maintainer     : {mnt}
First Submitted: {fsb}
Last Updated   : {upd}
Description    : {dsc}
""").format(cat=DS.categories[int(pkg['CategoryID'])],
            nme=pkg['Name'],

def jsonreq(self, rtype, arg, prot='http'):
        """Makes a request and returns plain JSON data.

:Arguments: request type, argument (package name), protocol.
:Input: none.
:Output: none.
:Returns: JSON data from the API.
:Exceptions: requests.exceptions.*, PBError.
:Message codes: ERR1001."""
        r = requests.get(self.rpc.format(prot, rtype, arg))
        if r.status_code != 200:
            raise PBError(_('[ERR1001] AUR: HTTP Error {0}').format(
                r.status_code))

        return r.text

"""Extracts an AUR tarball.

:Arguments: filename.
:Input: none.
:Output: none.
:Returns: file count.
:Exceptions: PBError, IOError.
:Message codes: ERR3151."""
        thandle = tarfile.open(filename, 'r:gz')
        thandle.extractall()
        names = thandle.getnames()
        thandle.close()
        if names != []:
            return len(names)
        else:
            raise PBError(_('[ERR3151] extract: no files extracted'))

def jsonmultiinfo(self, args, prot='http'):
        """Makes a multiinfo request and returns plain JSON data.

:Arguments: a list of packages, protocol.
:Input: none.
:Output: none.
:Returns: JSON data from the API.
:Exceptions: requests.exceptions.*, PBError.
:Message codes: ERR1001."""
        urlargs = '&arg[]=' + '&arg[]='.join(args)
        r = requests.get(self.mrpc.format(prot, urlargs))
        if r.status_code != 200:
            raise PBError(_('[ERR1001] AUR: HTTP Error {0}').format(
                r.status_code))

        return r.text

localdb = H.get_localdb()
                    pkg = localdb.get_pkg(pkgname)
                    aurversion = self.utils.info(pkgname)['Version']
                    if pkg is None:
                        fancy_error2(_('[ERR3451] validation: NOT \
installed'))
                    else:
                        if pyalpm.vercmp(aurversion, pkg.version) > 0:
                            fancy_error2(_('[ERR3452] validation: \
outdated {0}').format(pkg.version))
                        else:
                            fancy_msg2(_('[INF3450] validation: \
installed {0}').format(pkg.version))
            elif build_result[0] >= 0 and build_result[0] <= 15:
                os.chdir('../')
                raise PBError(_('[ERR3402] Something went wrong.  \
EC={0} EM={1}').format(build_result[0], build_result[1]))
            elif build_result[0] == 16:
                os.chdir('../')
                fancy_warning(_('[WRN3401] Building more AUR packages is \
required.'))
                for pkgname2 in build_result[1]:
                    self.auto_build(pkgname2, validate, performdepcheck,
                                    makepkginstall)
                self.auto_build(pkgname, validate, performdepcheck,
                                makepkginstall)
        except PBError as inst:
            fancy_error(str(inst))

:Arguments: URL, filename for saving, protocol.
:Input: none.
:Output: none.
:Returns: bytes downloaded.
:Exceptions:
    PBError, IOError, requests.exceptions.*
:Message codes: ERR3101, ERR3102."""
        r = requests.get(self.aururl.format(prot, urlpath))

        # Error handling.
        if r.status_code != 200:
            raise PBError(_('[ERR3102] download: HTTP Error {0}').format(
                r.status_code))
        elif r.headers['content-length'] == '0':
            raise PBError(_('[ERR3101] download: 0 bytes downloaded'))

        f = open(filename, 'wb')
        f.write(r.content)
        f.close()
        return r.headers['content-length']