一般最好使用BeautifulSoup之类的解析器从html中提取额外数据，而不是正则表达式，因为很难重现BeautifulSoup的精度；但是，您可以尝试使用纯正则表达式：
import re
url = 'https://free-proxy-list.net/'
headers = {'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_5) AppleWebKit/537.36 (KHTML, like Gecko) Cafari/537.36'}
source = str(requests.get(url, headers=headers, timeout=10).text)
data = [list(filter(None, i))[0] for i in re.findall('<td class="hm">(.*?)</td>|<td>(.*?)</td>', source)]
groupings = [dict(zip(['ip', 'port', 'code', 'using_anonymous'], data[i:i+4])) for i in range(0, len(data), 4)]
样本输出（实际长度为300）：
[{'ip': '47.88.242.10', 'port': '80', 'code': 'SG', 'using_anonymous': 'anonymous'}, {'ip': '118.189.172.136', 'port': '80', 'code': 'SG', 'using_anonymous': 'elite proxy'}, {'ip': '147.135.210.114', 'port': '54566', 'code': 'PL', 'using_anonymous': 'anonymous'}, {'ip': '5.148.150.155', 'port': '8080', 'code': 'GB', 'using_anonymous': 'elite proxy'}, {'ip': '186.227.8.21', 'port': '3128', 'code': 'BR', 'using_anonymous': 'anonymous'}, {'ip': '49.151.155.60', 'port': '8080', 'code': 'PH', 'using_anonymous': 'anonymous'}, {'ip': '52.170.255.17', 'port': '80', 'code': 'US', 'using_anonymous': 'anonymous'}, {'ip': '51.15.35.239', 'port': '3128', 'code': 'NL', 'using_anonymous': 'elite proxy'}, {'ip': '163.172.27.213', 'port': '3128', 'code': 'GB', 'using_anonymous': 'elite proxy'}, {'ip': '94.137.31.214', 'port': '8080', 'code': 'RU', 'using_anonymous': 'anonymous'}]
编辑：连接 ip 和端口，遍历每个分组并使用字符串格式：
final_groupings = [{'full_ip':"{ip}:{port}".format(**i)} for i in groupings]
输出：
[{'full_ip': '47.88.242.10:80'}, {'full_ip': '118.189.172.136:80'}, {'full_ip': '147.135.210.114:54566'}, {'full_ip': '5.148.150.155:8080'}, {'full_ip': '186.227.8.21:3128'}, {'full_ip': '49.151.155.60:8080'}, {'full_ip': '52.170.255.17:80'}, {'full_ip': '51.15.35.239:3128'}, {'full_ip': '163.172.27.213:3128'}, {'full_ip': '94.137.31.214:8080'}]