Python 목록에서 요소를 찾고 조작하는 방법: 효율적인 기술에 대한 가이드

if 3 in [1, 2, 3]:  # True

matches = [x for x in lst if x > 6]  # List comprehension
matches = (x for x in lst if x > 6)  # Generator expression

for item in lst:
    if fulfills_some_condition(item):
        break

first_match = next(x for x in lst if fulfills_some_condition(x))  # May raise StopIteration

first_match = next((x for x in lst if fulfills_some_condition(x)), None)  # Returns `None` if no match found

list_index = [1, 2, 3].index(2)  # 1

[1, 2, 3, 2].index(2)  # 1

duplicate_indices = [i for i, x in enumerate([1, 2, 3, 2]) if x == 2]  # [1, 3]