isupper(), islower() 함수이용하여 문자열의 대소문자 변경하기

def switchcase(string):

switchcaseStr = ""

for index in range(len(string)):

# Condition : lowercase letter, replace lowercase letter to uppercase letter

if (string[index].islower()):

asciiIndex = ord(string[index]) - 32

switchcaseStr += chr(asciiIndex)

# Condition : uppercase letter, replace uppercase letter to lowercase letter

elif (string[index].isupper()):

asciiIndex = ord(string[index]) + 32

switchcaseStr += chr(asciiIndex)

# Condition : non alphabetical letter, leave it the letter

else:

switchcaseStr += string[index]

return switchcaseStr

print (switchcase("Hi Cassie! COLLEGE station weather is REALLY HoT"))

Python 3.6.1 (default, Dec 2015, 13:05:11)
[GCC 4.8.2] on linux
   
hI cASSIE! college STATION WEATHER IS really hOt