I am programming with Python pygame at the moment.

Like many, I wondered about code folding a la vim.

Without adding a minor mode, I am using

M-<n> C-x $

, where <n> is one of 1, 5, 11 .. since I am using four space Python indentation. Selective display folds lines up to a certain leading indentation.

C-x $ runs the command set-selective-display (found in global-map),
which is an interactive compiled Lisp function in ‘simple.el’.

It is bound to C-x $.

(set-selective-display ARG)

Set ‘selective-display’ to ARG; clear it if no arg.
When the value of ‘selective-display’ is a number > 0,
lines whose indentation is >= that value are not displayed.
The variable ‘selective-display’ has a separate value for each buffer.

Withstanding I use Emacs for its extensibility, I prefer a builtin that takes one arguement.

It is kind of ugly to have to specify k * n + 1 with k levels of n space indentation.

Rather than applying a minor hack, my heart tells me the mistake here is Python.