• 20230117

在终端输入以下命令 ：
$ brew install python3

Mac ~ % brew install python3
Running `brew update --auto-update`...
==> Homebrew is run entirely by unpaid volunteers. Please consider donating:
  https://github.com/Homebrew/brew#donations

==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).

==> Fetching dependencies for python@3.10: gdbm, mpdecimal, ca-certificates, openssl@1.1, readline, sqlite and xz
==> Fetching gdbm
==> Downloading https://ghcr.io/v2/homebrew/core/gdbm/manifests/1.23
######################################################################## 100.0%
==> Downloading https://ghcr.io/v2/homebrew/core/gdbm/blobs/sha256:72bf08b82cb8f
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
######################################################################## 100.0%
==> Fetching mpdecimal
==> Downloading https://ghcr.io/v2/homebrew/core/mpdecimal/manifests/2.5.1
######################################################################## 100.0%
==> Downloading https://ghcr.io/v2/homebrew/core/mpdecimal/blobs/sha256:91f795d7
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
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==> Fetching ca-certificates
==> Downloading https://ghcr.io/v2/homebrew/core/ca-certificates/manifests/2023-
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==> Downloading https://ghcr.io/v2/homebrew/core/ca-certificates/blobs/sha256:11
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
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==> Fetching openssl@1.1
==> Downloading https://ghcr.io/v2/homebrew/core/openssl/1.1/manifests/1.1.1s
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==> Downloading https://ghcr.io/v2/homebrew/core/openssl/1.1/blobs/sha256:096c56
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
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==> Fetching readline
==> Downloading https://ghcr.io/v2/homebrew/core/readline/manifests/8.2.1
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==> Downloading https://ghcr.io/v2/homebrew/core/readline/blobs/sha256:abe9d3f3e
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
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==> Fetching sqlite
==> Downloading https://ghcr.io/v2/homebrew/core/sqlite/manifests/3.40.1
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==> Downloading https://ghcr.io/v2/homebrew/core/sqlite/blobs/sha256:d3092d3c942
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
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==> Fetching xz
==> Downloading https://ghcr.io/v2/homebrew/core/xz/manifests/5.4.1
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==> Downloading https://ghcr.io/v2/homebrew/core/xz/blobs/sha256:619b87932c5393a
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
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==> Fetching python@3.10
==> Downloading https://ghcr.io/v2/homebrew/core/python/3.10/manifests/3.10.9
######################################################################## 100.0%
==> Downloading https://ghcr.io/v2/homebrew/core/python/3.10/blobs/sha256:12dd2d
==> Downloading from https://pkg-containers.githubusercontent.com/ghcr1/blobs/sh
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==> Installing dependencies for python@3.10: gdbm, mpdecimal, ca-certificates, openssl@1.1, readline, sqlite and xz
==> Installing python@3.10 dependency: gdbm
==> Pouring gdbm--1.23.ventura.bottle.tar.gz
🍺  /usr/local/Cellar/gdbm/1.23: 24 files, 955.4KB
==> Installing python@3.10 dependency: mpdecimal
==> Pouring mpdecimal--2.5.1.ventura.bottle.tar.gz
🍺  /usr/local/Cellar/mpdecimal/2.5.1: 71 files, 2MB
==> Installing python@3.10 dependency: ca-certificates
==> Pouring ca-certificates--2023-01-10.all.bottle.tar.gz
==> Regenerating CA certificate bundle from keychain, this may take a while...
🍺  /usr/local/Cellar/ca-certificates/2023-01-10: 3 files, 216.9KB
==> Installing python@3.10 dependency: openssl@1.1
==> Pouring openssl@1.1--1.1.1s.ventura.bottle.tar.gz
🍺  /usr/local/Cellar/openssl@1.1/1.1.1s: 8,101 files, 18.5MB
==> Installing python@3.10 dependency: readline
==> Pouring readline--8.2.1.ventura.bottle.tar.gz
🍺  /usr/local/Cellar/readline/8.2.1: 50 files, 1.7MB
==> Installing python@3.10 dependency: sqlite
==> Pouring sqlite--3.40.1.ventura.bottle.tar.gz
🍺  /usr/local/Cellar/sqlite/3.40.1: 11 files, 4.4MB
==> Installing python@3.10 dependency: xz
==> Pouring xz--5.4.1.ventura.bottle.tar.gz
🍺  /usr/local/Cellar/xz/5.4.1: 95 files, 1.6MB
==> Installing python@3.10
==> Pouring python@3.10--3.10.9.ventura.bottle.tar.gz
Error: The `brew link` step did not complete successfully
The formula built, but is not symlinked into /usr/local
Could not symlink bin/2to3
Target /usr/local/bin/2to3
already exists. You may want to remove it:
  rm '/usr/local/bin/2to3'

To force the link and overwrite all conflicting files:
  brew link --overwrite python@3.10

To list all files that would be deleted:
  brew link --overwrite --dry-run python@3.10

Possible conflicting files are:
/usr/local/bin/2to3 -> /Library/Frameworks/Python.framework/Versions/3.11/bin/2to3
/usr/local/bin/idle3 -> /Library/Frameworks/Python.framework/Versions/3.11/bin/idle3
/usr/local/bin/pydoc3 -> /Library/Frameworks/Python.framework/Versions/3.11/bin/pydoc3
/usr/local/bin/python3 -> /Library/Frameworks/Python.framework/Versions/3.11/bin/python3
/usr/local/bin/python3-config -> /Library/Frameworks/Python.framework/Versions/3.11/bin/python3-config
==> /usr/local/Cellar/python@3.10/3.10.9/bin/python3.10 -m ensurepip
==> /usr/local/Cellar/python@3.10/3.10.9/bin/python3.10 -m pip install -v --no-d
==> Caveats
Python has been installed as
  /usr/local/bin/python3

Unversioned symlinks `python`, `python-config`, `pip` etc. pointing to
`python3`, `python3-config`, `pip3` etc., respectively, have been installed into
  /usr/local/opt/python@3.10/libexec/bin

You can install Python packages with
  pip3 install <package>
They will install into the site-package directory
  /usr/local/lib/python3.10/site-packages

tkinter is no longer included with this formula, but it is available separately:
  brew install python-tk@3.10

See: https://docs.brew.sh/Homebrew-and-Python
==> Summary
🍺  /usr/local/Cellar/python@3.10/3.10.9: 3,108 files, 56.4MB
==> Running `brew cleanup python@3.10`...
Disable this behaviour by setting HOMEBREW_NO_INSTALL_CLEANUP.
Hide these hints with HOMEBREW_NO_ENV_HINTS (see `man brew`).
==> Caveats
==> python@3.10
Python has been installed as
  /usr/local/bin/python3

Unversioned symlinks `python`, `python-config`, `pip` etc. pointing to
`python3`, `python3-config`, `pip3` etc., respectively, have been installed into
  /usr/local/opt/python@3.10/libexec/bin

You can install Python packages with
  pip3 install <package>
They will install into the site-package directory
  /usr/local/lib/python3.10/site-packages

tkinter is no longer included with this formula, but it is available separately:
  brew install python-tk@3.10

See: https://docs.brew.sh/Homebrew-and-Python

不过你在终端输入 :~ mac$ python -V
依旧是 Python 2.7.10
或者是 zsh: command not found: python