Dear Guix,

I'd like to update our package for python-anndata.  For this I needed to add a
few more packages that are used in the test suite of python-anndata.

I attached the patches.  Note that for python-zarr I disabled the tests because
the majority of the tests need external packages.  We could add all dependencies
to make the test suite work, but that requires a significant amount of work (for
example, the Azure SDK for Python is one of the external dependencies).

Is it OK to move forward with the disabled test suite for python-zarr?

Thanks!

Kind regards,
Roel Janssen