Two types of downloading errors not mentioned in readme

[linzhiqiu]

I encountered these downloading errors not mentioned in readme on two different clusters:

'''
[Errno 2] No such file or directory: '/tmp/3b8307be-030b-4da9-8792-695b265c4519.mp4'
ERROR: [youtube] 4zlrc3gx5TU: Video unavailable
[Errno 2] No such file or directory: '/tmp/9d45c696-2486-40c1-b64d-0be0d21961c4.mp4'
ERROR: [youtube] 52If1n8HcBk: Private video. Sign in if you've been granted access to this video
[Errno 2] No such file or directory: '/tmp/0b8196fe-2cb1-42c3-a37a-78b0e1c43f4e.mp4'
ERROR: [youtube] Hn7W9IyqaaA: Requested format is not available. Use --list-formats for a list of available formats
[Errno 2] No such file or directory: '/tmp/4334c5ce-b18e-4ae4-815a-c8ccc3a471bf.mp4'
ERROR: [youtube] Buv6xdqzsUg: Requested format is not available. Use --list-formats for a list of available formats
[Errno 2] No such file or directory: '/tmp/57fdaff0-04ce-4f1b-bab3-fb3073614d51.mp4'
ERROR: [youtube] -6r04gCLMWw: Requested format is not available. Use --list-formats for a list of available formats
[Errno 2] No such file or directory: '/tmp/152c7025-fda9-46c1-bb1a-df3e480f3a14.mp4'
ERROR: [youtube] 1pDMN3jhfI4: Requested format is not available. Use --list-formats for a list of available formats
[Errno 2] No such file or directory: '/tmp/34f60d94-cb2e-40ca-88f0-c097bfcac4b5.mp4'
'''

and

"""
ERROR: You have requested merging of multiple formats but ffmpeg is not installed. Aborting due to --abort-on-error
[Errno 2] No such file or directory: '/tmp/dffa338f-c7b5-4abb-b9b1-085d7a6c0b7d.mp4'
ERROR: You have requested merging of multiple formats but ffmpeg is not installed. Aborting due to --abort-on-error
[Errno 2] No such file or directory: '/tmp/54fa081f-f8b7-46e8-8675-f006520e5fb6.mp4'
ERROR: You have requested merging of multiple formats but ffmpeg is not installed. Aborting due to --abort-on-error
[Errno 2] No such file or directory: '/tmp/27231622-f570-49c8-88fa-42956833895f.mp4'
[download] 0.0% of 16.10MiB at 78.32KiB/s ETA 03:30ERROR: You have requested merging of multiple formats but ffmpeg is not installed. Aborting due to --abort-on-error
[download] 0.8% of 16.10MiB at 1.15MiB/s ETA 00:13[Errno 2] No such file or directory: '/tmp/fdce0ab7-3354-4978-ac27-2b527004c6f1.mp4'
[download] 6.2% of 16.10MiB at 6.97MiB/s ETA 00:02ERROR: You have requested merging of multiple formats but ffmpeg is not installed. Aborting due to --abort-on-error
[Errno 2] No such file or directory: '/tmp/8003179d-30f2-41ca-ab24-c9b7bf2d9aa3.mp4'
ERROR: You have requested merging of multiple formats but ffmpeg is not installed. Aborting due to --abort-on-error
"""

How to resolve these errors?

[taiyouZhang]

same to me

[yangmin666]

Have you solved it? Same problem.

[landroche]

i have solved the same problem"ERROR: You have requested merging of multiple formats but ffmpeg is not installed"
by following this kkroening/ffmpeg-python#174 (comment)