text: export const estonia = {
      name: 'Estonia',
      codes: ['EE', 'EST', '233'],
      calcFn: (vat) => {
          let total = 0;
          let expect;
          // Extract the next digit and multiply by the counter.
          for (let i = 0; i < 8; i++) {
              total += Number(vat.charAt(i)) * estonia.rules.multipliers.common[i];
          }
          // Establish check digits using modulus 10.
          total = 10 - (total % 10);
          if (total === 10)
              total = 0;
          // Compare it with the last character of the VAT number. If it's the same, then it's valid.
          expect = Number(vat.slice(8, 9));
          return total === expect;
      },
      rules: {
          multipliers: {
              common: [3, 7, 1, 3, 7, 1, 3, 7]
          },
          regex: [/^(EE)(10\d{7})$/]
      }
  };
  