Can not install the submodules like pip install -e d4rl

[liuzhi136]

I try to install this project with the commands listed in the home page but get the following errors.

(psl) leoliu@amax:~/gitRepos/planseqlearn-master$ pip install -e d4rl/
Obtaining file:///home/leoliu/gitRepos/planseqlearn-master/d4rl
Preparing metadata (setup.py) ... done
Collecting dm_control@ git+git://github.com/deepmind/dm_control@master#egg=dm_control (from d4rl==1.1)
Cloning git://github.com/deepmind/dm_control (to revision master) to /tmp/pip-install-hsjo0gez/dm-control_c265d048f94a48d1afc708cfc35ba756
Running command git clone --filter=blob:none --quiet git://github.com/deepmind/dm_control /tmp/pip-install-hsjo0gez/dm-control_c265d048f94a48d1afc708cfc35ba756
fatal: unable to connect to github.com:
github.com[0: 20.205.243.166]: errno=Connection timed out

All submodules in this repo encounter this type of error.
Does any can help me to solve it?
Thanks!