how to update software not in repo

[Moltke]

I know it's been marked as solved and everything, but I just wanted to add that this /usr/bin/env: ‘python’: No such file or directory message error, doesn't have to do with python not being installed, but youtube-dl still looking for python2, which is deprecated and that's why when you installed the pkg python-is-python2 youtube-dl worked. You can verify with

Code:

cat $(which youtube-dl)

for python3 you should see

Code:

 moltke  ~  cat $(which youtube-dl)
#!/usr/bin/python3

if you instead see this

Code:

#!/usr/bin/env python

which you probably will, then youtube-dl is indeed looking for python2. This pkg http://archive.ubuntu.com/ubuntu/ubuntu/...u1_all.deb has that line set properly pointing to python3.

Also, this

Code:

youtube-dl: error: youtube-dl's self-update mechanism is disabled on Debian.
Please update youtube-dl using apt(8).
See https://packages.debian.org/sid/youtube-dl for the latest packaged version.

Is because of youtube api changes made by google, which they do quite often.