youtube_dl KeyError 'key' - python-3.x

Question

Hello I am trying to download youtube videos with the following code
import youtube_dl
import tempfile
youtube_links = ['https://www.youtube.com/watch?v=668nUCeBHyY']
with tempfile.TemporaryDirectory() as tempdir:
opts = {
'format': 'best',
'outtmpl': f'{tempdir}/%(id)s.%(ext)s',
'noplaylist': True,
'postprocessors': [{
'preferredcodec': 'mp4'
}]
}
ydl = youtube_dl.YoutubeDL(opts)
try:
meta = ydl.extract_info(
youtube_links,
download=True
)
except Exception as e:
raise e
else:
print(f"Downloaded to {tempdir}/{meta['id']}.{meta['ext']}")
However this raises an error:
<path>>py -3.8 test.py
Traceback (most recent call last):
File "test.py", line 14, in <module>
ydl = youtube_dl.YoutubeDL(opts)
File "C:\Users\User\AppData\Local\Programs\Python\Python38\lib\site-packages\youtube_dl\YoutubeDL.py", line 429, in __init__
pp_class = get_postprocessor(pp_def_raw['key'])
KeyError: 'key'
And none of the examples told me anything about a key I have to pass, nor can I find anything about it, what am I doing wrong?

Answer 1

In a nutshell, try this:
'postprocessors': [{
'key':'FFmpegMetadata',
'preferredcodec': 'mp4'
}]
There are lots of keys, so if it's not working, check out this: https://github.com/ytdl-org/youtube-dl/blob/master/youtube_dl/postprocessor/__init__.py
The trick is that the keys listed inside the file are not usable because you gotta drop the "PP" part!!
FYI:
It seems you are trying to get video? Then you should try the documented style: https://github.com/ytdl-org/youtube-dl/
You have to look at the "Functions" yourself and guess what parameters you should put here: https://github.com/ytdl-org/youtube-dl/blob/master/youtube_dl/YoutubeDL.py In fact, somewhere in this link says, "check out the init.py for key information."