gistfile1.txt

import time
import os
rows, columns = os.popen('stty size', 'r').read().split()

def many_x_wave(n,sleep_time):
    while True:
        for i in xrange(1,n+1):
            print i*"X"
            time.sleep(sleep_time)
        for i in xrange(n,0,-1):
            print i*"X"
            time.sleep(sleep_time)

def single_x_wave(n,sleep_time):
    while True:
        for i in xrange(1,n+1):
            print (i-1)*" "+"X"
            time.sleep(sleep_time)
        for i in xrange(n,0,-1):
            print (i-1)*" "+"X"
            time.sleep(sleep_time)

#single_x_wave(int(columns),.01)
many_x_wave(int(columns),.01)