您更正的模式是 HERE

我会将这样的文本分成块，然后在每个块中找到匹配项:

I would break text like that into BLOCKS and then find the matches in each block:

import csv
import re

fieldnames = ['AREA', 'MCC', 'MNC']

re_fields = re.compile(r'({})\s*=\s*([^,]+),'.format('|'.join(fieldnames)))

with open(fn) as f_input:
    data=f_input.read()
    
for block in re.finditer(r'(?<=ADD IUACCAREALST:)(.*?)(?=ADD IUACCAREALST:|\Z)', data, flags=re.S | re.M):
    print(re_fields.findall(block.group(1)))

打印:

[('AREA', 'RA'), ('MCC', '"510"'), ('MNC', '"28"')]
[('AREA', 'RA'), ('MCC', '"510"'), ('MNC', '"28"')]

此时，使用每个元组列表创建一个形成该 csv 记录的字典；将其写入 csv 文件.大功告成！

At that point, use each list of tuples to create a dict forming that csv record; write it to the csv file. Done!