message: Update excel-sheet-column-title.py
diff: @@ -7,12 +7,10 @@ class Solution(object):
  :type n: int
  :rtype: str
  """
  - result, dvd = "", n
  -
  - while dvd:
  - result += chr((dvd - 1) % 26 + ord('A'))
  - dvd = (dvd - 1) / 26
  -
  - return result[::-1]
  -
  + result = []
  + while n:
  + result += chr((n-1)%26 + ord('A'))
  + n = (n-1)//26
  + result.reverse()
  + return "".join(result)
  