First lines of every single scraper/downloader I write in Python

cacheddownload.py

def download(url):
    "Use request to retrieve URL's content. It sleeps 1s before starting."
    time.sleep(3)               # Can't bring the scraped site down :)
    return requests.get(url).text


def saverequest(path, req):
    "Write `req' into file pointed by `path'. Assumes `req' is in UTF-8."
    io.open(path, 'w', encoding='utf-8').write(req)
    return req


def cachepath(url):
    "Generate a file path for saving the URL in disk"
    return './tmp/scraper-' + url.replace('/', '-').replace(':', '-')


def cachedurl(url):
    "Retrieve URL and cache it into disk"
    name = cachepath(url)
    if os.path.exists(name):
        return True, io.open(name, 'r', encoding='utf-8').read()
    else: return False, saverequest(name, download(url))


thing = cachedurl("http://link.c/foo")[1]