IBAN (International Bank Account Number)

const re = new RegExp("^[A-Z]{2}\\d{2}[A-Z0-9]{11,30}$", "");
const input = "GB29NWBK60161331926819";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));

import re

pattern = re.compile(r"^[A-Z]{2}\d{2}[A-Z0-9]{11,30}$")
input_text = "GB29NWBK60161331926819"
for m in pattern.finditer(input_text):
    print(m.group(0))

package main

import (
	"fmt"
	"regexp"
)

func main() {
	re := regexp.MustCompile(`^[A-Z]{2}\d{2}[A-Z0-9]{11,30}$`)
	input := `GB29NWBK60161331926819`
	for _, match := range re.FindAllString(input, -1) {
		fmt.Println(match)
	}
}