[code python]
   group_name = input("Введите название чего-то")
   url = f"https://api.vk.com/method/wall.get?domain={group_name}&count=20&access_token={token}&v=5.52"
    req = requests.get(url)
    src = req.json()

  with open(f"{group_name}/{group_name}.json", "w", encoding="utf-8") as file:
  json.dump(src, file, indent=4, ensure_ascii=False)

   with open(f"{group_name}/data.csv", "w", encoding="utf-8" ) as file:
            writer = csv.writer(file,delimiter='&')
            posts = src["response"]["items"]
            for fresh_post_id in posts:
                writer.writerow([fresh_post_id["text"].rstrip(),fresh_post_id["id"]]) #вот здесь не убирает перенос
                print(fresh_post_id["text"].rstrip(),fresh_post_id["id"]) #и вот здесь тоже не убирает перенос

[/code]

  
>>> import sys
>>> 
>>> lst = ['a', 'b', 'c', 'd']
>>> 
>>> string = '&'.join(lst)
>>> 
>>> print(string, end='', file=sys.stdout)
a&b&c&d>>>

 "text": "Продам... Недорого...\nПисать в личку...",

posts = src["response"]["items"]
for fresh_post_id in posts:
    writer.writerow(fresh_post_id["text"])

  
>>> dct = {
...     'text': 'Продам... Недорого...\nПисать в личку...'
... }
>>> 
>>> text = dct['text'].replace('\n', ' ')
>>> text
'Продам... Недорого... Писать в личку...'
>>>