DocOnce offers a special format for exercises, problems, projects, and examples:
===== Problem: Flip a Coin =====
label{demo:ex:1}
files=flip_coin.py, flip_coin.pdf
solutions=mysol.txt, mysol_flip_coin.py
keywords = random numbers; Monte Carlo simulation
!bsubex
Make a program that simulates flipping a coin $N$ times.
!bhint
Use `r = random.random()` and define head as `r <= 0.5`.
!ehint
!esubex
!bsubex
Compute the probability of getting heads.
!bans
0.5.
!eans
!esubex