code: def int_to_alpha(n, upper=True):
      "Generates alphanumeric labels of form A-Z, AA-ZZ etc."
      casenum = 65 if upper else 97
      label = ''
      count= 0
      if n == 0: return str(chr(n + casenum))
      while n >= 0:
          mod, div = n % 26, n
          for _ in range(count):
              div //= 26
          div %= 26
          if count == 0:
              val = mod
          else:
              val = div
          label += str(chr(val + casenum))
          count += 1
          n -= 26**count
      return label[::-1f int_to_alpha(n, upper=True):
      "Generates alphanumeric labels of form A-Z, AA-ZZ etc."
      casenum = 65 if upper else 97
      label = ''
      count= 0
      if n == 0: return str(chr(n + casenum))
      while n >= 0:
          mod, div = n % 26, n
          for _ in range(count):
              div //= 26
          div %= 26
          if count == 0:
              val = mod
          else:
              val = div
          label += str(chr(val + casenum))
          count += 1
          n -= 26**count
      return label[::-1]
docs: Generates alphanumeric labels of form A-Z, AA-ZZ etc.