package apt-xapian-index 0.46ubuntu1 failed to install/upgrade: subprocess installed pre-removal script returned error exit status 127

screen not working properly
no laucher
no navbar at top

ProblemType: Package
DistroRelease: Ubuntu 15.04
Package: apt-xapian-index 0.46ubuntu1
ProcVersionSignature: Ubuntu 3.19.0-21.21-generic 3.19.8
Uname: Linux 3.19.0-21-generic x86_64
ApportVersion: 2.17.2-0ubuntu1.1
Architecture: amd64
Date: Wed Jul 1 13:50:13 2015
DpkgTerminalLog:
 Removing apt-xapian-index (0.46ubuntu1) ...
 /var/lib/dpkg/info/apt-xapian-index.prerm: 6: /var/lib/dpkg/info/apt-xapian-index.prerm: pyclean: not found
 dpkg: error processing package apt-xapian-index (--remove):
  subprocess installed pre-removal script returned error exit status 127
DuplicateSignature: package:apt-xapian-index:0.46ubuntu1:subprocess installed pre-removal script returned error exit status 127
ErrorMessage: subprocess installed pre-removal script returned error exit status 127
InstallationDate: Installed on 2015-06-27 (4 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.17.25ubuntu1
 apt 1.0.9.7ubuntu4
SourcePackage: apt-xapian-index
Title: package apt-xapian-index 0.46ubuntu1 failed to install/upgrade: subprocess installed pre-removal script returned error exit status 127
UpgradeStatus: No upgrade log present (probably fresh install)