sWAP cASE

Switch case of all letters in a string.

You are given a string and your task is to swap cases. In other words, convert all lowercase letters to uppercase letters and vice versa.

For Example:

Www.HackerRank.com → wWW.hACKERrANK.COM
Pythonist 2 → pYTHONIST 2

Input Format:
A single line containing a string S.

Constraints:
* 0<len(S)<=1000

Output Format:

Print the modified string S.

Sample Input:
HackerRank.com presents "Pythonist 2".

Sample Output:
hACKERrANK.COM PRESENTS "pYTHONIST 2".

Code:

A = 'HackerRank.com presents "Pythonist 2".'
def swap_case(s):
    S = list(s)
    for _ in range(len(S)):
        if S[_] == S[_].lower():
            S[_] = S[_].upper()
        elif S[_] == S[_].upper():
            S[_] = S[_].lower()

    return ''.join(S)

print(swap_case(A))