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[galanakis]

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Question

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The question is how to add custom metadata in a file using the python API.

In the command line I can do:

/usr/local/bin/youtube-dl 'https://www.youtube.com/watch?v=ogmga3szhW8' -x \
 --postprocessor-args '-metadata title='"'"'Title'"'"' -metadata genre=TANGO'

In order to add genre and a title.

I am trying to do the same thing using the python API,
but after trying:

ydl_opts = {
    'format': 'bestaudio/best',
    'prefer_ffmpeg': True, 
    'postprocessors': [{'key': 'FFmpegExtractAudio'}, {'key':'FFmpegMetadata'}],
    'postprocessor_args' : ['-metadata title='"'"'Title'"'"' -metadata genre=TANGO']
}

with youtube_dl.YoutubeDL(ydl_opts) as ydl:
    ydl.download(['https://www.youtube.com/watch?v=_4rXBKN3V7Q'])

I get:

ERROR: audio conversion failed: Error splitting the argument list: Option not found

I could not find easily documentation on this feature, so please if anyone can give me a tip I would appreciate it.