[Cython] import relative cimport

[Christoph Groth]

Oh, something I forgot:

in Cython/Compiler/Parsing.py I find code that emits "Relative cimport
is not supported yet".  However, when I try to compile code which
includes a relative cimport, I do not get this error, but instead

from .graph.defs cimport gint
^
------------------------------------------------------------

kwant/_system.pyx:8:0: 'graph.defs.pxd' not found

Is this related to the behavior of Pyrex?  I tried creating a file
"graph.defs.pxd" but I was unable to make the above line compile.