# https://school.programmers.co.kr/learn/courses/30/lessons/120888/
# programmers, level0: 중복된 문자 제거, python3
def solution(my_string: str) -> str:
dict = {}
for x in my_string:
if x not in dict:
dict[x] = 1
return "".join(map(str, [x for x in dict]))
if __name__ == '__main__':
print(solution("people"))
print(solution("We are the world"))