Index Error

[AnonPoison]

I get this every time I run " python3 -m mediascraper.twitter Twitter "

Traceback (most recent call last):
File "", line 198, in _run_module_as_main
File "", line 88, in _run_code
File "/Users/ /Downloads/media-scraper-master/mediascraper/twitter.py", line 14, in
scraper.login('credentials.json')
File "/Users/ /Downloads/media-scraper-master/mediascrapers.py", line 444, in login
username = [u for u in usernames if u.get_attribute('class') == 'js-username-field email-input js-initial-focus'][0]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^
IndexError: list index out of range