package python-oneconf 0.3.7 failed to install/upgrade: subprocess new pre-removal script returned error exit status 1

just like the summary

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.3 LTS"

expected to not see this error
what happened instead? this error.

ProblemType: Package
DistroRelease: Ubuntu 14.04
Package: python-oneconf 0.3.7
ProcVersionSignature: Ubuntu 3.13.0-66.108-generic 3.13.11-ckt27
Uname: Linux 3.13.0-66-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.18
Architecture: amd64
Date: Wed Oct 28 23:32:19 2015
DuplicateSignature: package:python-oneconf:0.3.7:subprocess new pre-removal script returned error exit status 1
ErrorMessage: subprocess new pre-removal script returned error exit status 1
InstallationDate: Installed on 2010-12-20 (1773 days ago)
InstallationMedia: Ubuntu-Server 10.10 "Maverick Meerkat" - Release amd64 (20101007)
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.17.5ubuntu5.4
 apt 1.0.1ubuntu2.10
SourcePackage: oneconf
Title: package python-oneconf 0.3.7 failed to install/upgrade: subprocess new pre-removal script returned error exit status 1
UpgradeStatus: Upgraded to trusty on 2015-03-17 (225 days ago)