maze generation (slashdot related)

#!/usr/bin/python -O

from __future__ import unicode_literals

import sys
import random, array
import itertools as it
import operator as op

def powerset(s):
    "powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
    return it.chain.from_iterable(it.combinations(s, r) for r in xrange(len(s)+1))

def value(desc):
    return (68, 64, 4, 160, 128, 32, 0)[
        ('VERTICAL', 'UP', 'DOWN', 'HORIZONTAL', 'LEFT', 'RIGHT', None).index(desc)]

OTHERS= [reduce(op.or_, x, 0) for x in powerset((16, 8, 2, 1))]

def make_table():
    import unicodedata as ud, re
    matcher= re.compile('^BOX DRAWINGS LIGHT (\S+)(?: AND (\S+))?$')
    table= array.array(b'u', ' ')*256
    for char_index in xrange(0x2500, 0x257f):
        char= unichr(char_index)
        match= matcher.match(ud.name(char))
        if match:
            mg1= match.group(1)
            mg2= match.group(2)
            table_index= value(mg1) | value(mg2)
            for other in OTHERS:
                table[table_index | other]= char
    return table

def make_maze(rows, cols):
    table= make_table()
    last_row= [1] + [2]*cols
    for ix in xrange(rows):
        curr_row= [1] + [random.randrange(4) for _ in xrange(cols-2)] + [1]
        for idx in xrange(1, len(curr_row)):
            sys.stdout.write(table[
                64*last_row[idx-1]
                + 16*last_row[idx]
                + 4*curr_row[idx-1]
                + curr_row[idx]])
        sys.stdout.write('\n')
        last_row= curr_row

if __name__ == "__main__":
    make_maze(int(sys.argv[1]), int(sys.argv[2]))