maze.py

import random


def make_maze(columns=20, rows=20):

    columns = columns / 2
    rows = rows / 2

    visited = [[0] * columns + [1] for _ in range(rows)] + [[1] * (columns + 1)]
    ver = [["* "] * columns + ['*'] for _ in range(rows)] + [[]]
    hor = [["**"] * columns + ['*'] for _ in range(rows + 1)]

    def walk(x, y):
        visited[y][x] = 1
        d = [
            (x - 1, y),
            (x, y + 1),
            (x + 1, y),
            (x, y - 1)
        ]
        random.shuffle(d)
        for (xx, yy) in d:
            if visited[yy][xx]:
                continue
            if xx == x:
                hor[max(y, yy)][x] = "* "
            if yy == y:
                ver[y][max(x, xx)] = "  "
            walk(xx, yy)

    walk(
        random.randrange(columns),
        random.randrange(rows)
    )

    s = ""
    for (a, b) in zip(hor, ver):
        s += ''.join(a + ['\n'] + b + ['\n'])
    return s

if __name__ == '__main__':
    print(make_maze(columns=40, rows=40))