Python Eggs and problem with %{python_sitelib}

[Marcin Zajączkowski]

Hi,

Recently I was updating my python package in rawhide to be compatible
with Python Eggs and from an error in a log it seems that
%{python_sitelib} is not declared.
Is it really required to define that variable at the beginning of every
SPEC file (eventually use %{_libdir}/python*/site-packages/) or it
should be already defined in the system?

Sample log:
http://koji.fedoraproject.org/koji/getfile?taskID=351446&name=build.log

Regards
Marcin