code: protected static E164CountryCode parse(String line) throws IOException {
          try {
              int pos = line.indexOf(' ');
              if (pos < 0) throw new IOException("Invalid format, could not parse prefix");
              String prefix = line.substring(0, pos);
  
              // rest of line is iso
              String iso = line.substring(pos+1).trim();
  
              // was there a name?
              if (iso == null || iso.equals("")) {
                  throw new IOException("Country ISO was null or empty");
              }
  
              // create the new country code
              return new E164CountryCode(prefix, iso);
          } catch (Exception e) {
              throw new IOException("Failed while parsing country code for line: " + line, e);
          }
      }
docs: Parses Format: 1804 US