Please describe the problem.

Not really related to datalad -- thought to addurl youtube playlist

youtube-dl seems might be capable of doing it

Please provide any additional information below.

$> git annex addurl --debug 'https://www.youtube.com/playlist?list=PLBHioGD0U1Cjd-meZbEcz-9ZxK-mb50tZ'                                                            [2018-03-28 13:09:06.337738339] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","git-annex"]
[2018-03-28 13:09:06.34708705] process done ExitSuccess
[2018-03-28 13:09:06.347202003] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","show-ref","--hash","refs/heads/git-annex"]
[2018-03-28 13:09:06.35303272] process done ExitSuccess
[2018-03-28 13:09:06.353205536] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","log","refs/heads/git-annex..734b368eab4f39d8494671657977952b02a35d9a","--pretty=%H","-n1"]
[2018-03-28 13:09:06.359101486] process done ExitSuccess
[2018-03-28 13:09:06.360005167] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch"]
[2018-03-28 13:09:06.361006846] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","cat-file","--batch-check=%(objectname) %(objecttype) %(objectsize)"]
addurl https://www.youtube.com/playlist?list=PLBHioGD0U1Cjd-meZbEcz-9ZxK-mb50tZ 
[2018-03-28 13:09:06.409163359] call: wget ["-nv","--show-progress","--clobber","-c","-O","/tmp/testyt/.git/annex/tmp/URL--https&c%%www.youtube.com%playlis-5bc73cdf8dc8bd73b13addc290b160e6","https://www.youtube.com/playlist?list=PLBHioGD0U1Cjd-meZbEcz-9ZxK-mb50tZ","--user-agent","git-annex/6.20180316+gitg308f3ecf6-1~ndall+1"]
/tmp/testyt/.git/ann 100%[===================>] 211.54K  --.-KB/s    in 0.04s   
2018-03-28 13:09:06 URL:https://www.youtube.com/playlist?list=PLBHioGD0U1Cjd-meZbEcz-9ZxK-mb50tZ [216616/216616] -> "/tmp/testyt/.git/annex/tmp/URL--https&c%%www.youtube.com%playlis-5bc73cdf8dc8bd73b13addc290b160e6" [1]
[2018-03-28 13:09:06.844196402] process done ExitSuccess
[2018-03-28 13:09:06.845246148] read: youtube-dl ["https://www.youtube.com/playlist?list=PLBHioGD0U1Cjd-meZbEcz-9ZxK-mb50tZ","--get-filename","--no-warnings"]
[2018-03-28 13:09:40.643440496] process done ExitSuccess
[2018-03-28 13:09:40.644420015] call: youtube-dl ["https://www.youtube.com/playlist?list=PLBHioGD0U1Cjd-meZbEcz-9ZxK-mb50tZ","--no-playlist","--playlist-items","0","--max-filesize","9046842816"]
[youtube:playlist] PLBHioGD0U1Cjd-meZbEcz-9ZxK-mb50tZ: Downloading webpage
[download] Downloading playlist: Canonical Computation in Brains and Machines
[youtube:playlist] playlist Canonical Computation in Brains and Machines: Downloading 0 videos
[download] Finished downloading playlist: Canonical Computation in Brains and Machines
[2018-03-28 13:09:41.925771815] process done ExitSuccess

  youtube-dl did not put any media in its work directory, perhaps it's been configured to store files somewhere else?
failed
[2018-03-28 13:09:41.926669401] process done ExitSuccess
[2018-03-28 13:09:41.926951446] process done ExitSuccess
git-annex: addurl: 1 failed
git annex addurl --debug   6.49s user 0.32s system 18% cpu 35.834 total

importfeed supports youtube playlists, once you look up their rss feed. done --Joey