Teachable/Wistia playlist_index issue

[dban0001]

Checklist

• I'm reporting a broken site support
• I've verified that I'm running youtube-dl version 2020.03.08
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that all URLs and arguments with special characters are properly quoted or escaped
• I've searched the bugtracker for similar issues including closed ones

Verbose log

❯ youtube-dl "https://masterthehandpan.teachable.com/courses/enrolled/639354" --username "xxx" --password "xxx" -f mp4 -o "%(playlist_index)s-%(title)s" --verbose
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'https://masterthehandpan.teachable.com/courses/enrolled/639354', u'--username', u'PRIVATE', u'--password', u'PRIVATE', u'-f', u'mp4', u'-o', u'%(playlist_index)s-%(title)s', u'--verbose']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2020.03.08
[debug] Python version 2.7.16 (CPython) - Darwin-19.3.0-x86_64-i386-64bit
[debug] exe versions: ffmpeg 4.2.2, ffprobe 4.2.2, rtmpdump 2.4
[debug] Proxy map: {}
[generic] 639354: Requesting header
[redirect] Following redirect to https://masterthehandpan.teachable.com/p/kabecao
[generic] kabecao: Requesting header
WARNING: Falling back on generic information extractor.
[generic] kabecao: Downloading webpage
[generic] kabecao: Extracting information
[TeachableCourse] Downloading masterthehandpan.teachable.com login page
[TeachableCourse] Logging in to masterthehandpan.teachable.com
[TeachableCourse] kabecao: Downloading webpage
[download] Downloading playlist: Kabeção's Masterclass
[TeachableCourse] playlist Kabeção's Masterclass: Collected 53 video ids (downloading 53 of them)
[download] Downloading video 1 of 53
[Teachable] Downloading masterthehandpan.teachable.com login page
[Teachable] 11543789: Downloading webpage
[download] Downloading playlist: Welcome
[Teachable] playlist Welcome: Collected 1 video ids (downloading 1 of them)
[download] Downloading video 1 of 1
[Wistia] d7kyurhl02: Downloading JSON metadata
[debug] Invoking downloader on u'http://embed.wistia.com/deliveries/6c4cc5b1bc21a190fc6b039d29e4ae2b0fe4203d.bin'
[download] Destination: 1-Welcome
[download] 100% of 80.66MiB in 01:24
[download] Finished downloading playlist: Welcome
[download] Downloading video 2 of 53
[Teachable] 12224321: Downloading webpage
[download] Downloading playlist: Warmup Stretching and training all your fingers
[Teachable] playlist Warmup Stretching and training all your fingers: Collected 1 video ids (downloading 1 of them)
[download] Downloading video 1 of 1
[Wistia] 7frfhq0k1o: Downloading JSON metadata
[debug] Invoking downloader on u'http://embed.wistia.com/deliveries/d4b3e8ecb8ae77e9491f505443fc0ffb1b2dfef9.bin'
[download] Destination: 1-Warmup Stretching and training all your fingers
[download]  45.3% of 178.59MiB at  1.07MiB/s ETA 01:30^C
ERROR: Interrupted by user

Description

The playlist downloads correctly, but for each playlist item YouTube-dl detects a new playlist with one item each. This is inconvenient when using a different output format like -o "%(playlist_index)s-%(title)s.%(ext)s", as the playlist index will default to 1, e.g. 1-Welcome.mp4, 1-bla bla.mp4, etc.

[dstftw]

Use autonumber.