Excel Sheet Column Title

Given an integer columnNumber, return its corresponding column title as it appears in an Excel sheet.

For example:

A -> 1
B -> 2
C -> 3
...
Z -> 26
AA -> 27
AB -> 28 
...

Example 1:

Input: columnNumber = 1
Output: "A"

Example 2:

Input: columnNumber = 28
Output: "AB"

Example 3:

Input: columnNumber = 701
Output: "ZY"

Solution

class Solution:
    def convertToTitle(self, columnNumber: int) -> str:
        out = ''
        while columnNumber > 0:
            columnNumber -= 1
            out = chr(columnNumber % 26 + 65) + out
            columnNumber //= 26
        return out