cpython submodule upate fails on cpython/packages/rasterio

Trying to update git submodule to get cpython content :
```
$> git submodule update --init --recursive
...
fatal: remote error: upload-pack: not our ref fff416c6945b222f265fa268c4d56de34c8091dd
fatal: Fetched in submodule path 'cpython/packages/rasterio', but it did not contain fff416c6945b222f265fa268c4d56de34c8091dd. Direct fetching of that commit failed.
fatal: Failed to recurse into submodule path 'cpython'
```

I don't know how to fix this one. Maybe I didn't use the right git submodule update command ?

Start by examining the cpython/packages/rasterio submodule reference and rerunning the reported git submodule update --init --recursive command. Compare the requested commit fff416c6945b222f265fa268c4d56de34c8091dd with the submodule's available history. Done means the recursive submodule update completes successfully and retrieves the required cpython content.

Written by the indexing model from the issue text.