code: def validate(self, tracking_number):
          "Return True if this is a valid UPS tracking number."
          tracking_num = tracking_number[2:-1]
          odd_total = 0
          even_total = 0
  
          for ii, digit in enumerate(tracking_num.upper()):
              try:
                  value = int(digit)
              except ValueError:
                  value = int((ord(digit) - 63) % 10)
              if (ii + 1) % 2:
                  odd_total += value
              else:
                  even_total += value
  
          total = odd_total + even_total * 2
          check = ((total - (total % 10) + 10) - total) % 10
          return (check == int(tracking_number[-1:])f validate(self, tracking_number):
          "Return True if this is a valid UPS tracking number."
          tracking_num = tracking_number[2:-1]
          odd_total = 0
          even_total = 0
  
          for ii, digit in enumerate(tracking_num.upper()):
              try:
                  value = int(digit)
              except ValueError:
                  value = int((ord(digit) - 63) % 10)
              if (ii + 1) % 2:
                  odd_total += value
              else:
                  even_total += value
  
          total = odd_total + even_total * 2
          check = ((total - (total % 10) + 10) - total) % 10
          return (check == int(tracking_number[-1:]))
docs: Return True if this is a valid UPS tracking number.