How to use the scratch-l10n.default function in scratch-l10n

'} else {\n' +
            '    if (!req.http.Fastly-FF) {\n' +
            '        if (req.http.X-Forwarded-For) {\n' +
            '            set req.http.Fastly-Temp-XFF = req.http.X-Forwarded-For ", " client.ip;\n' +
            '        } else {\n' +
            '            set req.http.Fastly-Temp-XFF = client.ip;\n' +
            '        }\n' +
            '    } else {\n' +
            '        set req.http.Fastly-Temp-XFF = req.http.X-Forwarded-For;\n' +
            '    }\n' +
            '    set req.grace = 60s;\n' +
            '    if (req.http.Cookie:scratchlanguage) {\n' +
            '        set req.http.Accept-Language = req.http.Cookie:scratchlanguage;\n' +
            '    } else {\n' +
            '        set req.http.Accept-Language = accept.language_lookup("' +
                         Object.keys(languages).join(':') + '", ' +
                         '"en", ' +
                         'std.tolower(req.http.Accept-Language)' +
                     ');\n' +
            '    }\n' +
            '    if (req.url ~ "^(/projects/|/fragment/account-nav.json|/session/)" && ' +
            '!req.http.Cookie:scratchsessionsid) {\n' +
            '        set req.http.Cookie = "scratchlanguage=" req.http.Cookie:scratchlanguage;\n' +
            '    } else {\n' +
            '        return(pass);\n' +
            '    }\n' +
            '}\n';


        fastly.setCustomVCL(
            results.version,
            'recv-condition',