Mac 下 安装Python3

因为Mac系统自带Python2.7 所以我们开发要重新装Python3

直接运行下面就好

luohaotiandeMacBook-Pro:~ luohaotian$ which python
/usr/bin/python
luohaotiandeMacBook-Pro:~ luohaotian$ cd /usr/local/bin/
luohaotiandeMacBook-Pro:bin luohaotian$ ls
brew		lz4		perlthanks	ptardiff	svnrdump
cnpm		lz4c		piconv		ptargrep	svnserve
corelist	lz4cat		pl2pm		shasum		svnsync
cpan		node		pod2html	splain		svnversion
enc2xs		npm		pod2man		svn		unlz4
encguess	npx		pod2text	svnadmin	vue
h2ph		perl		pod2usage	svnbench	vue-init
h2xs		perl5.30.0	podchecker	svndumpfilter	vue-list
instmodsh	perlbug		podselect	svnfsfs		webpack
json_pp		perldoc		prove		svnlook		xsubpp
libnetcfg	perlivp		ptar		svnmucc		zipdetails
luohaotiandeMacBook-Pro:bin luohaotian$ python -V
Python 2.7.10
luohaotiandeMacBook-Pro:bin luohaotian$ brew search python3
==> Formulae
boost-python3              python3                    python@3
luohaotiandeMacBook-Pro:bin luohaotian$ brew install python3
Updating Homebrew...
==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).
==> Updated Formulae
jdupes                                   mk-configure

==> Installing dependencies for python: gdbm and xz
==> Installing python dependency: gdbm
==> Downloading https://homebrew.bintray.com/bottles/gdbm-1.18.1.mojave.bottle.1
######################################################################## 100.0%
==> Pouring gdbm-1.18.1.mojave.bottle.1.tar.gz
🍺  /usr/local/Cellar/gdbm/1.18.1: 20 files, 586.8KB
==> Installing python dependency: xz
==> Downloading https://homebrew.bintray.com/bottles/xz-5.2.4.mojave.bottle.tar.
==> Downloading from https://akamai.bintray.com/01/010667293df282c8bceede3bcd369
######################################################################## 100.0%
==> Pouring xz-5.2.4.mojave.bottle.tar.gz
🍺  /usr/local/Cellar/xz/5.2.4: 92 files, 1MB
==> Installing python
==> Downloading https://homebrew.bintray.com/bottles/python-3.7.3.mojave.bottle.
==> Downloading from https://akamai.bintray.com/25/25e0099852136c4ef1efd221247d0
######################################################################## 100.0%
==> Pouring python-3.7.3.mojave.bottle.tar.gz
==> /usr/local/Cellar/python/3.7.3/bin/python3 -s setup.py --no-user-cfg install
==> /usr/local/Cellar/python/3.7.3/bin/python3 -s setup.py --no-user-cfg install
==> /usr/local/Cellar/python/3.7.3/bin/python3 -s setup.py --no-user-cfg install
==> 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/libexec/bin

If you need Homebrew's Python 2.7 run
  brew install python@2

You can install Python packages with
  pip3 install <package>
They will install into the site-package directory
  /usr/local/lib/python3.7/site-packages

See: https://docs.brew.sh/Homebrew-and-Python
==> Summary
🍺  /usr/local/Cellar/python/3.7.3: 3,863 files, 59.8MB
==> Caveats
==> python
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/libexec/bin

If you need Homebrew's Python 2.7 run
  brew install python@2

You can install Python packages with
  pip3 install <package>
They will install into the site-package directory
  /usr/local/lib/python3.7/site-packages

See: https://docs.brew.sh/Homebrew-and-Python
luohaotiandeMacBook-Pro:bin luohaotian$ brew info python3
python: stable 3.7.3 (bottled), HEAD
Interpreted, interactive, object-oriented programming language
https://www.python.org/
/usr/local/Cellar/python/3.7.3 (3,863 files, 59.8MB) *
  Poured from bottle on 2019-06-04 at 18:24:52
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/python.rb
==> Dependencies
Build: pkg-config ✘
Required: gdbm ✔, openssl ✔, readline ✔, sqlite ✔, xz ✔
==> Options
--HEAD
	Install HEAD version
==> 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/libexec/bin

If you need Homebrew's Python 2.7 run
  brew install python@2

You can install Python packages with
  pip3 install <package>
They will install into the site-package directory
  /usr/local/lib/python3.7/site-packages

See: https://docs.brew.sh/Homebrew-and-Python
==> Analytics
install: 378,873 (30 days), 1,357,511 (90 days), 4,253,975 (365 days)
install_on_request: 181,954 (30 days), 660,530 (90 days), 2,431,795 (365 days)
build_error: 0 (30 days)
luohaotiandeMacBook-Pro:bin luohaotian$