Sun from APOD downloader

import time
from time import  gmtime, strftime
import os

imageURL = "http://sdo.gsfc.nasa.gov/assets/mov/depot/APOD/latest_APOD_HMIC_FR.jpg"

def retrieveImage(filename):
    cmd = "wget " + imageURL + " -O " + filename
    os.system(cmd)

try:
    timestr = strftime("%H-%M-%S", gmtime())
    filename = "APOD_HMIC_FR_" + timestr + ".jpg"
    retrieveImage(filename);
except:
    print("Error at " + timestr + ", trying one more time")
    time.sleep(15)
    try:
        timestr = strftime("%H-%M-%S", gmtime())
        filename = "APOD_HMIC_FR_" + timestr + ".jpg"
        retrieveImage(filename)
    except:
        print("Error at " + timestr)