Unicode error when downloading

[amirgershman]

$ python infoq_downloader.py http://www.infoq.com/presentations/db-history-data-processing\?utm_source\=infoq\&utm_medium\=videos_homepage\&utm_campaign\=videos_row2
Downloading HTML file
Traceback (most recent call last):
File "infoq_downloader.py", line 80, in
if not os.path.exists('{}/slides'.format(presentation_directory)):
UnicodeEncodeError: 'ascii' codec can't encode character u'\u2019' in position 31: ordinal not in range(128)

$ git log
Sun Oct 19 10:19:24 2014 +0200 dead91c (HEAD, origin/master, origin/HEAD, master) Merge pull request #14 from alefnula/py3 [Mohammad Tayseer]

[joncasdam]

+1 on this.
actually, with it happened when downloading a video with pt_br title.