循环数组，如果存在键值，则将1添加到结构化数组中

array = [
    {"key": "A", "value": 1},
    {"key": "B", "value": 2},
    {"key": "C", "value": 3},
]

key_to_find = "B"

for item in array:
    if item["key"] == key_to_find:
        item["found"] = 1
        break

[
    {"key": "A", "value": 1},
    {"key": "B", "value": 2, "found": 1},
    {"key": "C", "value": 3},
]