XS-Python-Version vs pyversions

[Ludovico Cavedon <ludovico.cavedon@gmail.com>]

Hi all,
I am working on packaging a python modules using python-support.

cddb warns me:
==========
WARNING:  Use of XS-Python-Version and XB-Python-Version fields in
debian/control is deprecated with pysupport method; use
debian/pyversions if you need to specify specific versions
==========

But on the other side [1] says:
"The addition of the XS-Python-Version/XB-Python-Version fields is
appreciated."

[1] http://wiki.debian.org/DebianPython/NewPolicy [+-]

I spent some time looking on ML archives and Debian wiki, but I could
not find a clear answer about which one is the preferred one. Using both
of them looks to me a useless replication of information.

What is the best practice?

Thank you in advance,
Ludovico