package python-crypto 2.6.1-6build1 failed to install/upgrade: subprocess new pre-removal script returned error exit status 1

[Removed by request]

saying something. i could not understand.

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: python-crypto 2.6.1-6build1
ProcVersionSignature: Ubuntu 4.4.0-63.84-generic 4.4.44
Uname: Linux 4.4.0-63-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.1-0ubuntu2.5
Architecture: amd64
Date: Sat Jul 22 19:30:38 2017
ErrorMessage: subprocess new pre-removal script returned error exit status 1
InstallationDate: Installed on 2016-03-05 (504 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.2
 apt 1.2.20
SourcePackage: python-crypto
Title: package python-crypto 2.6.1-6build1 failed to install/upgrade: subprocess new pre-removal script returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)