I’m facing this error while installing face_recognition in a virtualenv with Python 3.8.10 on Ubuntu 20.04.

ERROR: Failed building wheel for face-recognition-models
  Running setup.py clean for face-recognition-models
Failed to build dlib face-recognition-models
Installing collected packages: Click, numpy, dlib, face-recognition-models, face-recognition
    Running setup.py install for dlib ... error
    ERROR: Command errored out with exit status 1:
     command: '/home/badrelden/Desktop/test python sound/venv/bin/python3' -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-tai2snq9/dlib/setup.py'"'"'; __file__='"'"'/tmp/pip-install-tai2snq9/dlib/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-bhy0sde6/install-record.txt --single-version-externally-managed --compile --install-headers '/home/badrelden/Desktop/test python sound/venv/include/site/python3.8/dlib'
         cwd: /tmp/pip-install-tai2snq9/dlib/
    Complete output (8 lines):
    running install
    running build
    running build_py
    package init file 'tools/python/dlib/__init__.py' not found (or not a regular file)
    running build_ext
    
    ERROR: CMake must be installed to build dlib
    
    ----------------------------------------
ERROR: Command errored out with exit status 1: '/home/badrelden/Desktop/test python sound/venv/bin/python3' -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-tai2snq9/dlib/setup.py'"'"'; __file__='"'"'/tmp/pip-install-tai2snq9/dlib/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-bhy0sde6/install-record.txt --single-version-externally-managed --compile --install-headers '/home/badrelden/Desktop/test python sound/venv/include/site/python3.8/dlib' Check the logs for full command output.

>Solution :

ERROR: CMake must be installed to build dlib

This is the key part of the error message. You need to install cmake, which can be done by running sudo apt install cmake on Debian-based systems, including Ubuntu. After cmake is installed, you can rerun the pip install command.