countryCodeToEmoji method
Implementation
String countryCodeToEmoji(String countryCode) {
final int firstLetter = countryCode.codeUnitAt(0) - 0x41 + 0x1F1E6;
final int secondLetter = countryCode.codeUnitAt(1) - 0x41 + 0x1F1E6;
return String.fromCharCode(firstLetter) + String.fromCharCode(secondLetter);
}