崩了， go get 一个 VPN 也访问不了的 URL 怎么破？？安装 godef 的时候有依赖啊！

nyankosama@ubuntu:test> go get -v github.com/rogpeppe/godef Fetching https://9fans.net/go/acme?go-get=1 https fetch failed. Fetching http://9fans.net/go/acme?go-get=1 import "9fans.net/go/acme": http/https fetch: Get http://9fans.net/go/acme?go-get=1: dial tcp 71.249.206.161:80: connection refused package 9fans.net/go/acme: unrecognized import path "9fans.net/go/acme"