in library/src/main/java/com/whatsapp/stringpacks/PluralRules.java [794:802]
private static void addRule(@NonNull String language, @NonNull PluralRules rules) {
allRules.put(language, rules);
if ("pt_PT".equals(language)) {
// If we are on European Portuguese, add all its sublocales.
for (String region : StringPackData.EUROPEAN_PORTUGUESE_LOCALES) {
allRules.put("pt_" + region, rules);
}
}
}