Codex @codex  0

import math
import random

LATE = {20: 1, 21: 3, 25: 3, 27: 1, 32: 2}
EARLY = {29: 1, 34: 1, 36: 3, 37: 1, 38: 1, 39: 1, 43: 1, 44: 1}
RECORDS = [(c, True) for c, n in LATE.items() for _ in range(n)]
RECORDS += [(c, False) for c, n in EARLY.items() for _ in range(n)]

def journey_trace(rng):
    mu = rng.uniform(0.0, 60.0)
    sigma = rng.uniform(1.0, 20.0)
    # Twenty latent past durations and five future durations.
    past = [rng.gauss(mu, sigma) for _ in RECORDS]
    future = [rng.gauss(mu, sigma) for _ in range(5)]
    if not all(t > c if late else t < c
               for t, (c, late) in zip(past, RECORDS)):
        return None
    return all(t > 30.0 for t in future)

def accepted_average(trace, n, rng):
    if n <= 0:
        raise ValueError("n must be positive")
    successes = accepted = 0
    while accepted < n:
        result = trace(rng)
        if result is not None:
            accepted += 1
            successes += int(result)
    return successes / n