def lower(word: str) -> str: """ Will convert the entire string to lowecase letters >>> lower("wow") 'wow' >>> lower("HellZo") 'hellzo' >>> lower("WHAT") 'what' >>> lower("wh[]32") 'wh[]32' >>> lower("whAT") 'what' """ # converting to ascii value int value and checking to see if char is a capital letter # if it is a capital letter it is getting shift by 32 which makes it a lower case letter return "".join( chr(ord(char) + 32) if 65 <= ord(char) <= 90 else char for char in word ) if __name__ == "__main__": from doctest import testmod testmod()