install.py 文件源码

def _build_package_finder(self, options, index_urls, session):
        """
        Create a package finder appropriate to this install command.
        This method is meant to be overridden by subclasses, not
        called directly.
        """
        return PackageFinder(
            find_links=options.find_links,
            format_control=options.format_control,
            index_urls=index_urls,
            allow_external=options.allow_external,
            allow_unverified=options.allow_unverified,
            allow_all_external=options.allow_all_external,
            trusted_hosts=options.trusted_hosts,
            allow_all_prereleases=options.pre,
            process_dependency_links=options.process_dependency_links,
            session=session,
        )