Create a package finder appropriate to this list command.

def _build_package_finder(self, options, index_urls, session):
        """
        Create a package finder appropriate to this list command.
        """
        return PackageFinder(
            find_links=options.find_links,
            index_urls=index_urls,
            allow_all_prereleases=options.pre,
            trusted_hosts=options.trusted_hosts,
            session=session,
        )