Why does Vim run python2 while it's compiled with +python3?

Question

vim --version
VIM - Vi IMproved 8.0 (2016 Sep 12, compiled Jun 06 2019 17:31:41)
Included patches: 1-1453
Modified by pkg-vim-maintainers@lists.alioth.debian.org
Compiled by pkg-vim-maintainers@lists.alioth.debian.org
Huge version without GUI.  Features included (+) or not (-):
+comments          +libcall           -python            +vreplace
+conceal           +linebreak         +python3           +wildignore

I have ignored others in the list by just showing the -python and + python3.

$ python --version
Python 3.6.9

While in the vim I got:

$vim test.py    
:!python --version
    Python 2.7.17

Answer 1

When you do :!cmd you are running cmd on the shell. This has not much to do with vim. To check which version of python vim is using internally do :python3 import sys; print(sys.version) :python3 import sys; print(sys.version) inside vim.