I would argue that linking in Python happens at runtime and therefore, it is okay to distribute software that *could* potentially link to a GPL library, as long as we don't.  Of course, you may always distribute your source under the license of your choice, the only problem comes in with binaries.  If you distribute a binary linked against a GPL library, then the collected sources must be distributed under the terms of the GPL (which is fine in our case, because we have a more liberal license).