The interpreter doesn't run every line — it runs a path through your file, and a condition can make it skip lines entirely. Below is a real widget from epochai's own curriculum, not a flowchart diagram.
It's tempting to think of a Python file as a strict top-to-bottom script, every line running once, in order. That's true for straight-line code — but the moment a conditional shows up, the interpreter starts making choices about which lines to run at all, not just when to run them.
Inside an if/else, only one branch's lines ever execute per pass — the other
branch's lines are skipped completely, as if they weren't in the file. The line count on the page doesn't
change; the line count the interpreter actually visits does.
This is the real shape of "execution order": not a straight line down the file, but a path through it, decided live as the program runs. Watching that path get traced, line by line, is the fastest way to build an accurate mental model — much faster than reading the code and guessing.
Module 1 — Programming Fundamentals — covers variables, control flow, loops, functions, and debugging. Free, no card required.