当我跑的时候brew postinstall python3，失败了。
错误代码：
$ brew postinstall python@3.9 --debug
/usr/local/Homebrew/Library/Homebrew/brew.rb (Formulary::FormulaLoader): loading /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core/Formula/python@3.9.rb
==> Postinstalling python@3.9
==> /usr/local/Cellar/python@3.9/3.9.1_8/bin/python3 -m ensurepip
Last 15 lines from /Users/wangdi/Library/Logs/Homebrew/python@3.9/post_install.01.python3:
2021-02-09 21:23:55 +0800
/usr/local/Cellar/python@3.9/3.9.1_8/bin/python3
-m
ensurepip
Warning: The post-install step did not complete successfully
You can try again using:
brew postinstall python@3.9
==> An exception occurred within a child process:
BuildError: Failed executing: /usr/local/Cellar/python@3.9/3.9.1_8/bin/python3 -m ensurepip
/usr/local/Homebrew/Library/Homebrew/formula.rb:2108:in `block in system'
/usr/local/Homebrew/Library/Homebrew/formula.rb:2044:in `open'
/usr/local/Homebrew/Library/Homebrew/formula.rb:2044:in `system'
/usr/local/Homebrew/Library/Taps/homebrew/homebrew-core/Formula/python@3.9.rb:272:in `post_install'
/usr/local/Homebrew/Library/Homebrew/formula.rb:1058:in `block (2 levels) in run_post_install'
/usr/local/Homebrew/Library/Homebrew/formula.rb:900:in …