def get_column_letter(n: int) -> str:
	"""
	This function converts the column index to column letter
	1 to A,
	5 to E, etc
	:param n:
	:return:
	"""
	string = ""
	while n > 0:
		n, remainder = divmod(n - 1, 26)
		string = chr(65 + remainder) + string
	return string