Fancy unfinished script for random gifs

import random
import commands
import platform
import sys
# DEFS      #
def pickgif():
    ls = "%s slashbslash%sgifs%s" % (lscmd,seperator,seperator)
    print "doing %s" % ls
    ls = commands.getoutput(ls)
    items = ls.split("\n")
    gifs = {}
    i = 1
    for item in items:
        gifs[i] = item
        i = i + 1
    r = random.randrange(1,i,1)
    output = gifs[r]
    return output
# ENDDEFS
os = False
osversion = platform.system()
if osversion == "Darwin":
    lscmd = "ls"
    seperator = "/"
    opcmd = "open "
    os = True
if osversion == "Windows":
    lscmd = "dir"
    seperator = "\\"
    opcmd = ""
    os = True
if os == True:
    gif = pickgif()
if os == False:
    print "unsupported OS, Exitting"
    sys.exit()

command = "%s\"slashbslash%sgifs%s%s\"" % (opcmd,seperator,seperator,gif)

print command

commands.getoutput(command)