How to parse large text into a string?

Question

Python

Good day, toasters)
And I'm interested in such a question that I've been struggling with for 3 days and I can't overcome it.
There is the following code:

def get_html(url):
  html = requests.get(url)
  return html.text
def get_descriptions(html):
  description = ''
  soup = bs(html, 'lxml')
  description = soup.find('div', class_='item-description').text
  return description
file_desc = open('file.txt', 'a')
url = 'Какой-то сайт'
html = get_html(url)
result_descriptions = str(get_descriptions(html)).replace('\n', ' ').replace('@', '')
file_desc.writelines('{}\n'.format(result_descriptions))
file_desc.close()

The thing is that from some pages it takes a description and writes it down, and from some pages it gives the following error.

Picture with error

Tried like this:

file_desc.writelines('{}\n'.format(result_descriptions[0:450]))

But it helps in rare cases. I want everything to always work properly.
Help, please, who than can.

Answer 1

On Habré there is an article Unicode for Dummies
Must read for all pythonists and not only

Answer 2

description .encode('utf-8')

Answer 3

file_desc = open('file.txt', 'a', encoding='utf-8')