character encoding

[xczheng]

This is not an issue but can somebody help me understand why we have the encoding difference here:
After I get the info here:

info = ydl.extract_info('https://www.youtube.com/watch?t=4&v=BaW_jenozKc', download=True)
[youtube] BaW_jenozKc: Downloading webpage
[youtube] BaW_jenozKc: Downloading video info webpage
[youtube] BaW_jenozKc: Extracting video information
[youtube] BaW_jenozKc: Downloading MPD manifest
WARNING: "id" field is not a string - forcing string conversion
[download] youtube-dl test video ''_ä↭𝕐-BaW_jenozKc.mp4 has already been downloaded
[download] 100% of 1.74MiB

info['title']
u'youtube-dl test video "'/\\xe4\u21ad\U0001d550'
encodeFilename(info['title'])
'youtube-dl test video "'/\\xc3\xa4\xe2\x86\xad\xf0\x9d\x95\x90'

And the file downloaded on the disk has this:

os.listdir('.')
["youtube-dl test video ''_\xc3\xa4\xe2\x86\xad\xf0\x9d\x95\x90-BaW_jenozKc.mp4"]

Why do we have the encoding difference here? I am asking because I can not find the downloaded file by the filename '%(title)s-%(id)s.%(ext)s' % info.

'%(title)s-%(id)s.%(ext)s' % info
u'youtube-dl test video "'/\\xe4\u21ad\U0001d550-BaW_jenozKc.mp4'
os.path.getsize('%(title)s-%(id)s.%(ext)s' % info)
Traceback (most recent call last):
File "", line 1, in
File "/home2/goyoutub/python27/lib/python2.7/genericpath.py", line 57, in getsize
return os.stat(filename).st_size
OSError: [Errno 2] No such file or directory: 'youtube-dl test video "'/\\xc3\xa4\xe2\x86\xad\xf0\x9d\x95\x90-BaW_jenozKc.mp4'

[yan12125]

Try adding this line in the first line of your source code:

from __future__ import unicode_literals

[xczheng]

Thanks. However, they are already unicode but they are just different unicode.
By looking into the code, I find that the filename youtube-dl creates is from this function call:
ydl = youtube_dl.YoutubeDL(ydl_opts)
info = ydl.extract_info(special_url, download=True)
filename = ydl.prepare_filename(info)
the prepare_filename replaces some characters somehow. Now I can get the filename for the downloaded file when there is special characters in the title.