如何使用标志使用 findall-Python 仅返回一个组

Question

我正在使用艺术代码（如果可能的话？），我正在尝试使用findall 检索第三组正则表达式。我在findall 上阅读了官方文档，发现它返回的元组有点缺乏，我想传入一个标志来返回第三组，而不是 3 组的元组（前两个是占位符）。链接某些内容以仅返回名称（第三组）而不是之后迭代的最有效方法是什么？

import re, requests

rgx = r"([<][TDtd][>])|(target[=]new[>])(?P<the_deceased>[A-Z].*?)[,]"

urls = {2013: "http://www.killedbypolice.net/kbp2013.html",
        2014: "http://www.killedbypolice.net/kbp2014.html",
        2015: "http://www.killedbypolice.net/" }

names_of_the_dead = []

for url in urls.values():
    response = requests.get(url)
    content = response.content
    people_killed_by_police_that_year_alone = re.findall(rgx, content)
    for dead_person in people_killed_by_police_that_year_alone:
        names_of_the_dead.append(dead_person)

#dead_americans_as_string = ",".join(names_of_the_dead)
#print("RIP, {} since 2013:\n".format(len(names_of_the_dead)))
#print(dead_americans_as_string)

In [67]: names_of_the_dead
Out[67]: 
[('', 'target=new>', 'May 1st - Dec 31st'),
 ('', 'target=new>', 'Ricky Junior Toney'),
 ('', 'target=new>', 'William Jackson'),
 ('', 'target=new>', 'Bethany Lytle'),
 ('', 'target=new>', 'Christopher George'),

Answer 1

只需将第一个和第二个捕获组作为非捕获组。

rgx = r"(?:[<][TDtd][>])|(?:target[=]new[>])(?P<the_deceased>[A-Z].*?)[,]"

Answer 2

既然这是您要解析的 HTML 数据，为什么不使用专门的工具来解析它 - HTML Parser，例如 BeautifulSoup。想法是遍历表格行并获取第 4 列文本：

import requests
from bs4 import BeautifulSoup


urls = {2013: "http://www.killedbypolice.net/kbp2013.html",
        2014: "http://www.killedbypolice.net/kbp2014.html",
        2015: "http://www.killedbypolice.net/" }

names_of_the_dead = []

for url in urls.values():
    response = requests.get(url)
    soup = BeautifulSoup(response.content, "html.parser")

    for row in soup.select("table tr")[2:]:
        cells = row.find_all("td")
        if len(cells) > 3:
            names_of_the_dead.append(cells[3].text.split(",")[0].strip())

print(names_of_the_dead)