few tests failed on system with python2.4

[buriy]

warning: no previously-included files matching '*~' found anywhere in distribution
File "build/bdist.linux-x86_64/egg/paging/tests.py", line 18
self.assertEquals(page['previous_page'], num - 1 if num else False)
^
SyntaxError: invalid syntax
File "/usr/lib/python2.4/site-packages/django_paging-0.2.2-py2.4.egg/paging/tests.py", line 18
self.assertEquals(page['previous_page'], num - 1 if num else False)