import requests
import lxml, lxml.html

r = requests.get('http://www.lldj.com/pastresult.php')

html = lxml.html.fromstring(r.text)

imgs =  html.cssselect('img')

for x in imgs:
    src = x.attrib['src']
    if src.startswith('images/Balls'):
        print src[13:-4]

4
19
30
32
38
42
34