Pipes!

import argparse
import random

def sr(a) :
    t = (a >> 3 & 1) + (a & 1)
    if t == 0 : return 6
    else : return random.randint(2-t,3) << 1


pipes = ['','','',u'\u2557','',u'\u2550',u'\u2554',u'\u2566','',u'\u255d',u'\u2551',u'\u2563',u'\u255a',u'\u2569',u'\u2560',u'\u256c']

parser = argparse.ArgumentParser(description='No leaking pipe system generator')
parser.add_argument('width', metavar='W', type=int, help='Nuber of pipes in one row')
parser.add_argument('height', metavar='H', type=int, help='Number of rows')
nsp = parser.parse_args()

ps = [[]]

for i in range(nsp.height) :
    po = ''
    ps.append([])
    for j in range(nsp.width) :
        p = 0
        if i != 0 : p += (ps[i-1][j] >> 1 & 1) << 3
        else : p += random.randint(0,1) << 3
        if j != 0 : p += ps[i][j-1] >> 2 & 1
        else : p += random.randint(0,1)
        p += sr(p)
        ps[i].append(p)
        po += pipes[p]
    print(po)