Crashes when trying to upload duplicates

[mco13]

Uploading the same video twice results in

Traceback (most recent call last):
  File "youtube2mediawiki.py", line 416, in <module>
    import_youtube(youtube_id, opts.username, opts.password, opts.url)
  File "youtube2mediawiki.py", line 374, in import_youtube
    r = wiki.upload(filename, 'Imported from %s'%info['url'], description)
  File "youtube2mediawiki.py", line 342, in upload
    token = self.get_token(pagename, 'edit')
  File "youtube2mediawiki.py", line 337, in get_token
    })['query']['pages']['-1']['edittoken'])
KeyError: '-1'