下面方法亲测有效：
当然，前提是已经有proxy可以科学use google.
export all_proxy="socks5://127.0.0.1:1086"
$ git clone https://github.com/eugenp/tutorials.git
Cloning into 'tutorials'...
remote: Enumerating objects: 4, done.
remote: Counting objects: 100% (4/4), done.
remote: Compressing objects: 100% (4/4), done.
remote: Total 247784 (delta 0), reused 1 (delta 0), pack-reused 247780
Receiving objects: 100% (247784/247784), 286.03 MiB | 1.60 MiB/s, done.
Resolving deltas: 100% (82842/82842), done.
Updating files: 100% (21382/21382), done.
$