Traceback (most recent call last):
  File "/usr/lib/update-manager/check-new-release", line 25, in <module>
    init_proxy()
  File "/usr/lib/python2.6/dist-packages/DistUpgrade/utils.py", line 197, in init_proxy
    cnf = apt_pkg.configuration()
AttributeError: 'module' object has no attribute 'configuration'