ssh: connect to host github.com port 22: Connection timed out

ssh操作github时出现如下问题：

ssh: connect to host github.com port 22: Connection timed out
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

不知是否与之前的问题类似

但本次的解决方案是在.ssh/config下添加

Host github.com
 Hostname ssh.github.com
 Port 443