Packages were not found in the pkg-config search path

[ganzobtn]

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Overview

I upgraded python to 3.8 in my docker. When I try to install AV using pip3, it gives error

Actual behavior

{{
Complete output from command python setup.py egg_info:
Package libavformat was not found in the pkg-config search path.
Perhaps you should add the directory containing libavformat.pc' to the PKG_CONFIG_PATH environment variable No package 'libavformat' found Package libavcodec was not found in the pkg-config search path. Perhaps you should add the directory containing libavcodec.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libavcodec' found
Package libavdevice was not found in the pkg-config search path.
Perhaps you should add the directory containing libavdevice.pc' to the PKG_CONFIG_PATH environment variable No package 'libavdevice' found Package libavutil was not found in the pkg-config search path. Perhaps you should add the directory containing libavutil.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libavutil' found
Package libavfilter was not found in the pkg-config search path.
Perhaps you should add the directory containing libavfilter.pc' to the PKG_CONFIG_PATH environment variable No package 'libavfilter' found Package libswscale was not found in the pkg-config search path. Perhaps you should add the directory containing libswscale.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libswscale' found
Package libswresample was not found in the pkg-config search path.
Perhaps you should add the directory containing `libswresample.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libswresample' found
pkg-config could not find libraries ['avformat', 'avcodec', 'avdevice', 'avutil', 'avfilter', 'swscale', 'swresample'] }}