package python-pyinotify 0.9.4-1build1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[prashant rana]

unable to open software-center
when trying to install any app following error is shown in ubuntu :
Errors were encountered while processing:
 python-setuptools
 pep8
 python-coverage
 python-debtagshw
 python-distutils-extra
 python-pyinotify
 python-doit
 python-lxml
 python-scour
 python-unittest2
 python-piston-mini-client
 software-center-aptdaemon-plugins
 oneconf-common
 python3-oneconf
 oneconf
 python-oneconf
 software-center
E: Sub-process /usr/bin/dpkg returned an error code (1)

when i open terminal following things are shown :
No command 'dont' found, did you mean:
 Command 'font' from package 'libxgks-dev' (universe)
 Command 'doit' from package 'python-doit' (universe)
 Command 'dot' from package 'graphviz' (main)
dont: command not found

ProblemType: Package
DistroRelease: Ubuntu 14.04
Package: python-pyinotify 0.9.4-1build1
ProcVersionSignature: Ubuntu 3.16.0-62.82~14.04.1-generic 3.16.7-ckt23
Uname: Linux 3.16.0-62-generic x86_64
NonfreeKernelModules: nvidia wl
ApportVersion: 2.14.1-0ubuntu3.19
Architecture: amd64
Date: Fri Feb 26 22:19:13 2016
DuplicateSignature: package:python-pyinotify:0.9.4-1build1:subprocess installed post-installation script returned error exit status 1
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationDate: Installed on 2016-01-30 (26 days ago)
InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1)
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.17.5ubuntu5.5
 apt 1.0.1ubuntu2.11
SourcePackage: pyinotify
Title: package python-pyinotify 0.9.4-1build1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)