我已经使用 Ubuntu 多年了，但现在我完全搞不清楚到底发生了什么。
所有这些都表明我应该使用，python3.9但实际上却如此python3.10。请帮我调试一下。
这问题是我希望用指定路径update-alternatives替换pythonbin。在下面的例子中，我希望python链接到python3.9，但它没有替换它，我最终得到了 Ubuntu22.04 默认值，即python3.10。
下面的日志显示python链接到/usr/bin/python哪个链接到/usr/bin/python3.9哪个实际上是python3.9。但是，当我检查时python --version它实际上是3.10。
retyn@meland:~/projects/cracker$ python --version
Python 3.10.4
kretyn@meland:~/projects/cracker$ sudo update-alternatives --config python
There are 3 choices for the alternative python (providing /usr/bin/python).
Selection Path Priority Status
------------------------------------------------------------
0 /usr/bin/python3.9 3 auto mode
1 /usr/bin/python3.10 1 manual mode
2 /usr/bin/python3.8 2 manual mode
* 3 /usr/bin/python3.9 3 manual mode
Press <enter> to keep the current choice[*], or type selection number: 3
kretyn@meland:~/projects/cracker$ python --version
Python 3.10.4
kretyn@meland:~/projects/cracker$ python3 --version
Python 3.10.4
kretyn@meland:~/projects/cracker$ which python
/usr/bin/python
kretyn@meland:~/projects/cracker$ ll /usr/bin/python
lrwxrwxrwx 24 root 24 Sep 11:20 /usr/bin/python -> /etc/alternatives/python*
kretyn@meland:~/projects/cracker$ ll /etc/alternatives/python
lrwxrwxrwx 18 root 24 Sep 11:20 /etc/alternatives/python -> /usr/bin/python3.9*
kretyn@meland:~/projects/cracker$ /usr/bin/python3.9 --version
Python 3.9.14
kretyn@meland:~/projects/cracker$ /usr/bin/python --version
Python 3.9.14
kretyn@meland:~/projects/cracker$ python --version
Python 3.10.4
kretyn@meland:~/projects/cracker$ python
Python 3.10.4 (main, Jun 29 2022, 12:14:53) [GCC 11.2.0] on linux
检查type和type -a
kretyn@meland:~$ type python
python is aliased to `python3'
kretyn@meland:~$ type -a python
python is aliased to `python3'
python is /usr/bin/python
python is /bin/python
kretyn@meland:~$ /bin/python --version
Python 3.9.14
kretyn@meland:~$ /usr/bin/python --version
Python 3.9.14
kretyn@meland:~$ python3 --version
Python 3.10.4
^ 最后一个可能是原因。有一个别名python=python3，所以python被替换，但python3没有，这就是为什么python是python3.10。