Bringing numpy data in using VoxelCoefficient

Hello,
i want to bring data consisting of a 2-dim vector field into ngsolve and interpolate it to a grid function on my mesh.
I saw in other forum posts that this is possible using VoxelCoefficient and there was an example for scalar fields (Import numpy array into GridFunction - Kunena).
I tried to do this for the components of my field and “glue” them together using a normal Coefficient function, but the vectors seem to point in wrong directions.
I have trouble understanding the arguments of VoxelCoefficient (e.g. VoxelCoefficient((0,0), (1,1), u1, linear=True) ). What do the first two tuple actually mean?
Help would be really appreciated,
NGUnsolved

help (VoxelCoefficientFunction) 

This was what I was looking for.
It worked with both 2D and 3D.
Nice function.