mim source config and proxy info config

[Bannerli]

We try to use mmcv to do build our models.
Considering the fact that large scale training is deployed on the cloud, we have hardly resolved the pip source issues, which means we could use CLI "pip install xxxx" in our cloud-native containers.
But the problem is that, we could use "pip install mim", but "min install mmcv >= 0.6.0" goes wrong. It seems that the "mim" has the resource accessible problem. Anyway, "pip install mmcv" may be useful, but the version could not be pointed.
We guess that the "source of mim" should be config in the specific node of our private cloud cluster or other methods.
So I turn to you guys for help, what may be the root cause and how to address the lib downloading hardship.
Thanks~