'Give an url a score which can be used to choose preferred URLs
for a given project release.'

def score_url(self, url):

    t = urlparse(url)
    basename = posixpath.basename(t.path)
    compatible = True
    is_wheel = basename.endswith('.whl')
    if is_wheel:
        compatible = is_compatible(Wheel(basename), self.wheel_tags)
    return ((t.scheme != 'https'), ('pypi.python.org' in t.netloc), is_wheel, compatible, basename)
