def prefer_url(self, url1, url2):
        """
        Choose one of two URLs where both are candidates for distribution
        archives for the same version of a distribution (for example,
        .tar.gz vs. zip).

        The current implementation favours https:// URLs over http://, archives
        from PyPI over those from other locations, wheel compatibility (if a
        wheel) and then the archive name.
        """
        result = url2
        if url1:
            s1 = self.score_url(url1)
            s2 = self.score_url(url2)
            if s1 > s2:
                result = url1
            if result != url2:
                logger.debug('Not replacing %r with %r', url1, url2)
            else:
                logger.debug('Replacing %r with %r', url1, url2)
        return result

        Choose one of two URLs where both are candidates for distribution
        archives for the same version of a distribution (for example,
        .tar.gz vs. zip).

        The current implementation favours https:// URLs over http://, archives
        from PyPI over those from other locations, wheel compatibility (if a
        wheel) and then the archive name.
        
product/gradle-plugin/src/main/python/pip/_vendor/distlib/locators.py