Прочитать html файл - Python

Формулировка задачи:

Доброго времени суток! Нужно найти в html файле и записать в txt текст между тегами span

#!/usr/bin/env python
# -*- coding: utf-8 -*-
out = open('out.txt','w')
for i in range(1, 30):
    name_file = str(i) + '.html'
    f = open(name_file, 'r', encoding= 'utf8')
    for line in f:
        line_file = f.readline()
        star = line_file.find('<span>') + 6
        end = line_file.find('</span>')
        temp = line_file[star:end:1]
        out.writelines(temp)
        line_file = ''
        star = ''
        end = ''
    name_file = ''
    f.close()
    line_file = ''
    star =''
    end = ''
out.close()

Выдает такую ошибку

Traceback (most recent call last):
  File "C:/Users/NOUT/Desktop/teams/147.py", line 7, in <module>
    for line in f:
  File "C:\Users\NOUT\Miniconda3\lib\codecs.py", line 321, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x9e in position 2591: invalid start byte

Решение задачи: «Прочитать html файл»

textual
                            Листинг программы 
                        

                            import asyncio
import aiohttp
from lxml import html
 
 
@asyncio.coroutine
def fetch_page(url):
    response = yield from aiohttp.request('GET', url)
    content = yield from response.read()
    page = html.fromstring(content)
    result.extend([x.text for x in page.cssselect('table#teamsboard tr td.hidden-xs span') if x.text])
 
result = []
loop = asyncio.get_event_loop()
tasks = [fetch_page('http://2016.ufoctf.ru/teams/{}'.format(x)) for x in range(1,31)]
loop.run_until_complete(asyncio.wait(tasks))
loop.close()
 
print(set(result))
                        