docs: private static String replaceLeadingZero(String generated) {
          if (generated.charAt(0) == '0') {
              // find number > 0 as replacement to avoid leading zero numbers
              int replacement = 0;
              while (replacement == 0) {
                  replacement = generator.nextInt(10);
              }
              
              return replacement + generated.substring(1);
          } else {
              return generated;
          }
      }