在我的MacOS Big Sur上安装Python 3.6.13时，使用命令pyenv install 3.6.13，出现以下错误

MacBook-Pro-2:cache fancy$ pyenv install 3.6.5
python-build: use openssl from homebrew
python-build: use readline from homebrew
Installing Python-3.6.5...
python-build: use readline from homebrew
python-build: use zlib from xcode sdk

BUILD FAILED (OS X 11.4 using python-build 20180424)

Inspect or clean up the working tree at /var/folders/jv/jhykqkbn709g4pcn4978jxyc0000gn/T/python-build.20210812173758.79132
Results logged to /var/folders/jv/jhykqkbn709g4pcn4978jxyc0000gn/T/python-build.20210812173758.79132.log

Last 10 log lines:
./Modules/posixmodule.c:8210:15: error: implicit declaration of function 'sendfile' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
        ret = sendfile(in, out, offset, &sbytes, &sf, flags);
              ^
./Modules/posixmodule.c:10432:5: warning: code will never be executed [-Wunreachable-code]
    Py_FatalError("abort() called from Python code didn't abort!");
    ^~~~~~~~~~~~~
1 warning and 1 error generated.
make: *** [Modules/posixmodule.o] Error 1
make: *** Waiting for unfinished jobs....
1 warning generated.

解决的办法：

1. brew reinstall zlib bzip2
2. sudo rm -rf /Library/Developer/CommandLineTools
3. xcode-select --install
4. CFLAGS="-I$(brew --prefix openssl)/include -I$(brew --prefix bzip2)/include -I$(brew --prefix readline)/include -I$(xcrun --show-sdk-path)/usr/include" LDFLAGS="-L$(brew --prefix openssl)/lib -L$(brew --prefix readline)/lib -L$(brew --prefix zlib)/lib -L$(brew --prefix bzip2)/lib" pyenv install --patch 3.6.5 < <(curl -sSL https://github.com/python/cpython/commit/8ea6353.patch\?full_index\=1)