Roulette Wheel simulation

roulette_wheel.py

"""Roulette wheel simulation."""

from random import randrange


def wheel_spin() -> int:
    """Return result of roulette wheel spin.

    Returns
    -------
    tuple
        The winning number and its colour.
    """
    number = randrange(37)
    return (number, get_color(number))


def get_color(number: int) -> str:
    """Return the colour of the roulette wheel cell.

    Wheel numbers are in a specified order, and alternate
    between red and black, excluding the number 0 which is
    green.
    
    Returns
    -------
    str
        The colour associated with number.
    
    Raises
    ------
    ValueError
        When number is out of range.
    """
    # Layout of numbers on a "single zero" wheel,
    # starting with "red 32" and excluding zero.
    non_zero_wheel_numbers = (
        32, 15, 19, 4, 21, 2, 25, 17, 34, 6, 27, 13, 36,
        11, 30, 8, 23, 10, 5, 24, 16, 33, 1, 20, 14,
        31, 9, 22, 18, 29, 7, 28, 12, 35, 3, 26)
    colors = ("red", "black")

    if number == 0:
        return "green"

    try:
        index = non_zero_wheel_numbers.index(number)
    except ValueError as exc:
        raise ValueError (f"{number} is out of range. {exc}")

    return colors[index % 2]


# Test it.
for _ in range(10):
    result = wheel_spin()
    print(f"Number: {result[0]} colour: {result[1]}")