Ubuntu上python版本查看
$ python -V Python 2.7.12
1.安裝3.7
添加源
sudo add-apt-repository ppa:deadsnakes/ppa
檢查更新
sudo apt-get update
安裝python3.7
sudo apt-get install python3.7
安裝pip3
sudo apt install python3-pip
2.使用 update-alternatives 來為整個系統更改Python 版本
查看python替代版本信息
~$ update-alternatives --display python
但是結果為
update-alternatives: error: no alternatives for python
python的替代版本尚未被update-alternatives
查看python的位置
$ whereis python python: /usr/bin/python2.7 /usr/bin/python3.7 /usr/bin/python3.5m /usr/bin/python3.7m /usr/bin/python3.5 /usr/bin/python /usr/lib/python2.7 /usr/lib/python3.7 /usr/lib/python3.5 /etc/python2.7 /etc/python3.7 /etc/python3.5 /etc/python /usr/local/lib/python2.7 /usr/local/lib/python3.7 /usr/local/lib/python3.5 /usr/share/python /usr/share/man/man1/python.1.gz
更新一下替代列表
$ sudo update-alternatives --install /usr/bin/python python /usr/bin/python2.7 1 update-alternatives: using /usr/bin/python2.7 to provide /usr/bin/python (python) in auto mode baby@ubuntu:~$ sudo update-alternatives --install /usr/bin/python python /usr/bin/python3.7 2 update-alternatives: using /usr/bin/python3.7 to provide /usr/bin/python (python) in auto mode
查看python替代版本信息
$ update-alternatives --display python python - auto mode link best version is /usr/bin/python3.7 link currently points to /usr/bin/python3.7 link python is /usr/bin/python /usr/bin/python2.7 - priority 1 /usr/bin/python3.7 - priority 2
查看python版本
$ python -V Python 3.7.9
3.切換版本
切換到2.7
$ sudo update-alternatives --config python There are 2 choices for the alternative python (providing /usr/bin/python). Selection Path Priority Status ------------------------------------------------------------ * 0 /usr/bin/python3.7 2 auto mode 1 /usr/bin/python2.7 1 manual mode 2 /usr/bin/python3.7 2 manual mode Press <enter> to keep the current choice[*], or type selection number: 1 update-alternatives: using /usr/bin/python2.7 to provide /usr/bin/python (python) in manual mode baby@ubuntu:~$ python -V Python 2.7.12
pip版本
$ pip -V pip 8.1.1 from /usr/lib/python2.7/dist-packages (python 2.7)
切換到3.7
sudo update-alternatives --config python There are 2 choices for the alternative python (providing /usr/bin/python). Selection Path Priority Status ------------------------------------------------------------ 0 /usr/bin/python3.7 2 auto mode * 1 /usr/bin/python2.7 1 manual mode 2 /usr/bin/python3.7 2 manual mode Press <enter> to keep the current choice[*], or type selection number: 2 update-alternatives: using /usr/bin/python3.7 to provide /usr/bin/python (python) in manual mode baby@ubuntu:~$ python -V Python 3.7.9
安裝pip
sudo apt install python3-pip
pip版本
pip -V pip 8.1.1 from /usr/lib/python3/dist-packages (python 3.7)
pip的版本隨着python版本切換