'Try to find remote versions of this package using the
list_url and any other URLs described in the package file.'

def fetch_remote_versions(self):

    if (not self.all_urls):
        raise VersionFetchError(self.__class__)
    try:
        return spack.util.web.find_versions_of_archive(self.all_urls, self.list_url, self.list_depth)
    except spack.error.NoNetworkConnectionError as e:
        tty.die("Package.fetch_versions    couldn't    connect    to:", e.url, e.message)
