Fix Python – Running Python code in Vim

Question 1

I am writing Python code using Vim, and every time I want to run my code, I type this inside Vim:

:w !python

This gets frustrating, so I was looking for a quicker method to run Python code inside Vim. Executing Python scripts from a terminal maybe?
I am using Linux.

Question 2

How about adding an autocmd to your ~/.vimrc-file, creating a mapping:

autocmd FileType python map <buffer> <F9> :w<CR>:exec '!python3' shellescape(@%, 1)<CR>
autocmd FileType python imap <buffer> <F9> <esc>:w<CR>:exec '!python3' shellescape(@%, 1)<CR>

then you could press <F9> to execute the current buffer with python

Explanation:

autocmd: command that Vim will execute automatically on {event} (here: if you open a python file)
[i]map: creates a keyboard shortcut to <F9> in insert/normal mode
<buffer>: If multiple buffers/files are open: just use the active one
<esc>: leaving insert mode
:w<CR>: saves your file
!: runs the following command in your shell (try :!ls)
%: is replaced by the filename of your active buffer. But since it can contain things like whitespace and other “bad” stuff it is better practise not to write :python %, but use:
shellescape: escape the special characters. The 1 means with a backslash

TL;DR: The first line will work in normal mode and once you press <F9> it first saves your file and then run the file with python.
The second does the same thing, but leaves insert mode first

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