Linux python2 python3 切换

python2 python3 版本切换

# cat /etc/issue
Ubuntu 18.04.6 LTS \n \l
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# python --version
Python 2.7.17

# python2 --version
Python 2.7.17

# python3 --version
Python 3.6.9
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# whereis python
python: /usr/bin/python3.6m /usr/bin/python3.6 /usr/bin/python2.7 /usr/bin/python /usr/lib/python3.8 /usr/lib/python3.6 /usr/lib/python2.7 /usr/lib/python3.7 /etc/python3.6 /etc/python2.7 /etc/python /usr/local/lib/python3.6 /usr/local/lib/python2.7 /usr/share/python /usr/share/man/man1/python.1.gz
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# ls -lh /usr/bin/py*
-rwxr-xr-x 1 root root 7.7K Oct 25  2018 /usr/bin/py3clean
-rwxr-xr-x 1 root root  12K Oct 25  2018 /usr/bin/py3compile
lrwxrwxrwx 1 root root   31 Oct 25  2018 /usr/bin/py3versions -> ../share/python3/py3versions.py
-rwxr-xr-x 1 root root 4.1K Apr 16  2018 /usr/bin/pyclean
-rwxr-xr-x 1 root root  12K Apr 16  2018 /usr/bin/pycompile
lrwxrwxrwx 1 root root    8 Apr 16  2018 /usr/bin/pydoc -> pydoc2.7
-rwxr-xr-x 1 root root   79 Jul  1 23:56 /usr/bin/pydoc2.7
lrwxrwxrwx 1 root root    8 Oct 25  2018 /usr/bin/pydoc3 -> pydoc3.6
-rwxr-xr-x 1 root root   79 Jun 29 19:45 /usr/bin/pydoc3.6
lrwxrwxrwx 1 root root   12 Apr 16  2018 /usr/bin/pygettext -> pygettext2.7
-rwxr-xr-x 1 root root  22K Jul  1 23:56 /usr/bin/pygettext2.7
lrwxrwxrwx 1 root root   12 Oct 25  2018 /usr/bin/pygettext3 -> pygettext3.6
-rwxr-xr-x 1 root root  22K Jun 29 19:45 /usr/bin/pygettext3.6
-rwxr-xr-x 1 root root  392 Mar 22 19:03 /usr/bin/pyhtmlizer3
-rwxr-xr-x 1 root root  372 Jul 19 14:23 /usr/bin/pyjwt3
lrwxrwxrwx 1 root root    9 Apr 16  2018 /usr/bin/python -> python2.7
lrwxrwxrwx 1 root root    9 Apr 16  2018 /usr/bin/python2 -> python2.7
-rwxr-xr-x 1 root root 3.5M Jul  1 23:56 /usr/bin/python2.7
lrwxrwxrwx 1 root root    9 Oct 25  2018 /usr/bin/python3 -> python3.6
-rwxr-xr-x 2 root root 4.4M Jun 29 19:45 /usr/bin/python3.6
-rwxr-xr-x 2 root root 4.4M Jun 29 19:45 /usr/bin/python3.6m
-rwxr-xr-x 1 root root 1018 Oct 29  2017 /usr/bin/python3-jsondiff
-rwxr-xr-x 1 root root 3.6K Oct 29  2017 /usr/bin/python3-jsonpatch
-rwxr-xr-x 1 root root 1.4K May  2  2016 /usr/bin/python3-jsonpointer
-rwxr-xr-x 1 root root  398 Nov 16  2017 /usr/bin/python3-jsonschema
lrwxrwxrwx 1 root root   10 Oct 25  2018 /usr/bin/python3m -> python3.6m
lrwxrwxrwx 1 root root   29 Apr 16  2018 /usr/bin/pyversions -> ../share/python/pyversions.py
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# rm /usr/bin/python
# ln -s /usr/bin/python3.6 /usr/bin/python
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# python --version
Python 3.6.9
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