Refactoring random time values list generator function

Question

This function outputs random values in a list. Although I was happy to craft this solution from a more complex version, and it looks really cool to me, I wonder if it is an example of clean code.

How can it be improved, and what are other ways to write it?

def random_time_values() -> List[int]:
    ''' Generates random [hours, minutes, seconds] '''
    return [randint(*time) for time in [(0, 11), (0, 59), (0, 59)]]

Answer 1

What you've described and what you've written are two different things. You've described a function that outputs random times in a list, but it actually outputs a list of hour-minute tuple values randomly selected from a small, fixed set. Those can't both be true, so let's choose one - your description, of generating random times.

Why not:

• write a generator function that doesn't take an opinion on how many outputs you want; that way it can generate them lazily and the consumer can use e.g. islice
• make truly random times, with random hour, minute, second and microsecond fields, rather than choosing from a set

This could be as simple as:

import datetime
import random
from itertools import islice
from typing import Iterator


def random_time_values() -> Iterator[datetime.time]:
    base = datetime.datetime(1, 1, 1)
    while True:
        delta = datetime.timedelta(days=random.random())
        yield (base + delta).time()


def demo(n: int = 25) -> None:
    for t in islice(random_time_values(), n):
        print(t)


if __name__ == '__main__':
    demo()

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