title: youtube-dl playlist does not work anymore
body: <p>in the past I have downloaded Youtube's playlists with <em>youtube-dl</em> without any problem. However, now it downloads 0 videos. Could it have something to do with RIAA's DMCA takedown? Any suggestion or solution?
  The code I usually use is</p>
  <pre><code>youtube-dl -i -f mp4 --write-auto-sub --yes-playlist --output './%(title)s.%(ext)s' UUdp4_l1vPmpN-gDbUwhaRUQ
  </code></pre>
  <p>I have tried with the web URL or the playlist ID, both give me this result:</p>
  <pre><code>[youtube:playlist] UUdp4_l1vPmpN-gDbUwhaRUQ: Downloading webpage
  [download] Downloading playlist: UUdp4_l1vPmpN-gDbUwhaRUQ
  [youtube:playlist] playlist UUdp4_l1vPmpN-gDbUwhaRUQ: Downloading 0 videos
  [download] Finished downloading playlist: UUdp4_l1vPmpN-gDbUwhaRUQ
  </code></pre>
  <p>Also, I have uninstalled/updated youtube-dl (just in case) without improve.
  Thank you in advance,</p>