如何用Python遍历议员JSON数据并提取指定议员的CID？

需求说明 #

解析API返回的JSON数据，遍历州议员列表，根据姓氏（lastname）找到对应议员并提取其cid字段。

JSON数据结构 #

{
    "response": {
        "legislator": [
            {
                "@attributes": {
                    "cid": "N00029147",
                    "firstlast": "Andy Harris",
                    "lastname": "Harris",
                    "party": "R",
                    "office": "MD01",
                    "gender": "M",
                    "first_elected": "2010",
                    "exit_code": "0",
                    "comments": "",
                    "phone": "202-225-5311",
                    "fax": "202-225-0254",
                    "website": "http://harris.house.gov",
                    "webform": "https://harris.house.gov/contact-me/email-me",
                    "congress_office": "1533 Longworth House Office Building",
                    "bioguide_id": "H001052",
                    "votesmart_id": "19157",
                    "feccandid": "H8MD01094",
                    "twitter_id": "RepAndyHarrisMD",
                    "youtube_url": "https://youtube.com/RepAndyHarris",
                    "facebook_id": "AndyHarrisMD",
                    "birthdate": "1957-01-25"
                }
            },
            {
                "@attributes": {
                    "cid": "N00025482",
                    "firstlast": "Dutch Ruppersberger",
                    "lastname": "Ruppersberger",
                    "party": "D",
                    "office": "MD02",
                    "gender": "M",
                    "first_elected": "2002",
                    "exit_code": "0",
                    "comments": "",
                    "phone": "202-225-3061",
                    "fax": "202-225-3094",
                    "website": "http://ruppersberger.house.gov",
                    "webform": "http://ruppersberger.house.gov/contact-dutch/email-dutch",
                    "congress_office": "2416 Rayburn House Office Building",
                    "bioguide_id": "R000576",
                    "votesmart_id": "36130",
                    "feccandid": "H2MD02160",
                    "twitter_id": "Call_Me_Dutch",
                    "youtube_url": "https://youtube.com/ruppersberger",
                    "facebook_id": "184756771570504",
                    "birthdate": "1946-01-31"
                }
            }
        ]
    }
}

错误代码分析 #

你提供的代码存在几个关键问题：

• 错误遍历finance_response_info["response"]：response是字典，遍历它会得到键名而非议员数组。
• 错误访问议员数组：应通过finance_response_info["response"]["legislator"]访问，而非直接finance_response_info["legislator"]。
• 错误定位@attributes：@attributes是每个议员对象内的字典，并非顶层数组，无需[0]索引。
• 代码缩进错误：if语句后的逻辑未正确缩进。

错误代码：

finance_response_info = json.loads(financeInfo)
for v in finance_response_info["response"]:
    for a in finance_response_info["legislator"]:
        for b in finance_response_info["@attributes"][0]:
            if (b["lastname"] == lastName):
        candidateID = b["cid"]

正确实现代码 #

方式1：找到第一个匹配的议员CID #

import json

# 假设financeInfo是API返回的JSON字符串
finance_response_info = json.loads(financeInfo)
target_lastname = "Harris"  # 替换为目标姓氏
candidate_id = None

# 遍历议员列表
for legislator in finance_response_info["response"]["legislator"]:
    # 获取当前议员的属性字典
    attrs = legislator["@attributes"]
    if attrs["lastname"] == target_lastname:
        candidate_id = attrs["cid"]
        break  # 找到后立即停止遍历

if candidate_id:
    print(f"匹配到的CID: {candidate_id}")
else:
    print(f"未找到姓氏为{target_lastname}的议员")

方式2：收集所有同姓议员的CID #

如果存在多个同姓议员，可收集所有匹配结果：

import json

finance_response_info = json.loads(financeInfo)
target_lastname = "Harris"
candidate_ids = []

for legislator in finance_response_info["response"]["legislator"]:
    attrs = legislator["@attributes"]
    if attrs["lastname"] == target_lastname:
        candidate_ids.append(attrs["cid"])

if candidate_ids:
    print(f"匹配到的CID列表: {candidate_ids}")
else:
    print(f"未找到姓氏为{target_lastname}的议员")

关键说明 #

• 正确定位议员数组：finance_response_info["response"]["legislator"]是存储所有议员的列表，直接遍历即可。
• 每个议员对象的属性都在@attributes字典中，直接提取该字典后即可访问lastname和cid字段。
• 根据需求选择停止遍历或收集所有结果，提升效率。

内容的提问来源于stack exchange，提问作者Nikhita