import sys
if sys.version_info >= (3,):
    import queue
    from urllib.request import Request, urlopen
else:
    import Queue as queue
    from urllib2 import Request, urlopen
import resource
import multiprocessing

def process(f):
    heap_size=10*1024*1024

    q = multiprocessing.Queue()
    def newf(f, q):
        rsrc = resource.RLIMIT_DATA
        resource.setrlimit(rsrc, (heap_size, heap_size))
        try:
            r = f()
            q.put(r)
        except Exception as e:
            q.put(e)
    p = multiprocessing.Process(target=newf, args=(f, q))
    p.start()
    p.join()
    try:
        v = q.get(block=False)
    except queue.Empty:
        assert False
    finally:
        q.close()
    if isinstance(v, Exception):
        raise v
    else:
        return v

def fetch_sandbox(f):
    def newf():
        replies = process(f)
        assert replies == 'ok', replies
    return newf

@fetch_sandbox
def fetch():
    url = 'http://python.org/'
    request = Request(url)
    fd = urlopen(request)
    return 'ok'

fetch()