code: def regon(self) -> str:
          
          regon_coeffs = (8, 9, 2, 3, 4, 5, 6, 7)
          regon_digits = [self.random.randint(0, 9) for _ in range(8)]
          sum_v = sum([nc * nd for nc, nd in
                       zip(regon_coeffs, regon_digits)])
          checksum_digit = sum_v % 11
          if checksum_digit > 9:
              checksum_digit = 0
          regon_digits.append(checksum_digit)
          return ''.join(str(d) for d in regon_digits)
docs: Generate random valid 9-digit REGON.
  
          :return: Valid 9-digit REGON