Python初学者， 求字典序最大字符

Question

问题是这样的，我的想法是这样的
str="ABCDEFGHIJKLMNOPQRSTUVWXYZ"

l=input()

n=list(l)

while len(n)!=0:

if eval(n[:2])<27:

    print(str[eval(n[0:2])-1],end="")

    n.remove(0,1)

else:

    n.remove(0)

    print(str[eval(n(0)-1)],end="")

Answer 1

l = '12324252'

while l:
    if int(l[:2]) < 27:
        print(chr(int(l[:2])+64), end="")
        l = l[2:]
    else:
        print(chr(int(l[:1])+64), end="")
        l = l[1:]