'For a given package name, returns a link to the download URL,
else returns None.
Related: https://github.com/Miserlou/Zappa/issues/398
Examples here: https://gist.github.com/perrygeo/9545f94eaddec18a65fd7b56880adbae'

def get_manylinux_wheel_url(self, package_name, package_version):

    url = 'https://pypi.python.org/pypi/{}/json'.format(package_name)
    try:
        res = requests.get(url, timeout=1.5)
        data = res.json()
        for f in data['releases'][package_version]:
            if f['filename'].endswith(self.manylinux_wheel_file_suffix):
                return f['url']
    except Exception as e:
        return None
    return None
