install fails python-5 dependency

For diagnostic purposes, please provide the output of the terminal commands

uname -a
lsb_release -crid
apt-cache policy
apt-cache policy gtk2-engines-pixbuf
apt-get --simulate install gtk2-engines-pixbuf python-mlt python-support

kanon@kanon-Vostro-1500:/etc/modprobe.d$ uname -a
Linux kanon-Vostro-1500 3.13.0-48-generic #80~precise1-Ubuntu SMP Thu Mar 12 19:30:36 UTC 2015 i686 i686 i386 GNU/Linux
kanon@kanon-Vostro-1500:/etc/modprobe.d$ lsb_release -crid
Distributor ID: Ubuntu
Description: Ubuntu 12.04.5 LTS
Release: 12.04
Codename: precise
kanon@kanon-Vostro-1500:/etc/modprobe.d$ apt-cache policy
Package files:
 100 /var/lib/dpkg/status
     release a=now
 500 http://download.opensuse.org/repositories/home:/klaussfreire:/debian/xUbuntu_12.04/ Packages
     release o=obs://build.opensuse.org/home:klaussfreire:debian/xUbuntu_12.04,n=xUbuntu_12.04,l=home:klaussfreire:debian,c=
     origin download.opensuse.org
 500 http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu/ precise/main i386 Packages
     release v=12.04,o=LP-PPA-ubuntu-wine,a=precise,n=precise,l=Wine Team PPA,c=main
     origin ppa.launchpad.net
 500 http://ppa.launchpad.net/tualatrix/ppa/ubuntu/ precise/main i386 Packages
     release v=12.04,o=LP-PPA-tualatrix,a=precise,n=precise,l=Ubuntu Tweak Stable PPA,c=main
     origin ppa.launchpad.net
 500 http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu/ precise/main Translation-en
 500 http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu/ precise/main i386 Packages
     release v=12.04,o=LP-PPA-sunab-kdenlive-release,a=precise,n=precise,l=kdenlive-release,c=main
     origin ppa.launchpad.net
 500 http://deb.opera.com/opera/ stable/non-free i386 Packages
     release o=Opera Software ASA,a=stable,n=stable,l=The Opera web browser,c=non-free
     origin deb.opera.com
 500 http://ppa.launchpad.net/openshot.developers/ppa/ubuntu/ precise/main i386 Packages
     release v=12.04,o=LP-PPA-openshot.developers,a=precise,n=precise,l=OpenShot: Stable PPA - Official Releases,c=main
     origin ppa.launchpad.net
 500 http://mega.nz/linux/MEGAsync/xUbuntu_12.04/ ./ Packages
     release o=obs://Mega/MEGAsync/xUbuntu_12.04,n=xUbuntu_12.04,l=MEGAsync,c=
     origin mega.nz
 500 ftp://ftp.videolan.org/pub/debian/stable/ ./ Packages
     release o=videolan,a=stable,n=stable,l=videolan,c=
     origin ftp.videolan.org
 500 http://archive.getdeb.net/ubuntu/ precise-getdeb/apps i386 Packages
     release v=12.04,o=GetDeb,a=precise-getdeb,n=precise-getdeb,l=GetDeb,c=apps
     origin archive.getdeb.net
 500 http://ppa.launchpad.net/ehoover/compholio/ubuntu/ precise/main Translation-en
 500 http://ppa.launchpad.net/ehoover/compholio/ubuntu/ precise/main i386 Packages
     release v=12.04,o=LP-PPA-ehoover-compholio,a=precise,n=precise,l=compholio,c=main
     origin ppa.launchpad.net
 500 http://extras.ubuntu.com/ubuntu/ precise/main i386 Packages
     release v=12.04,o=LP-PPA-app-review-board,a=precise,n=precise,l=Application Review Board PPA,c=main
     origin extras.ubuntu.com
 500 http://archive.canonical.com/ubuntu/ precise/partner Translation-en
 500 http://archive.canonical.com/ubuntu/ precise/partner i386 Packages
     release v=12.04,o=Canonical,a=precise,n=precise,l=Partner archive,c=partner
     origin archive.canonical.com
 500 http://security.ubuntu.com/ubuntu/ precise-security/universe Translation-en
 500 http://security.ubuntu.com/ubuntu/ precise-security/restricted Translation-en
 500 http://security.ubuntu.com/ubuntu/ precise-security/multiverse Translation-en
 500 http://security.ubuntu.com/ubuntu/ precise-security/main Translation-en
 500 http://security.ubuntu.com/ubuntu/ precise-security/multiverse i386 Packages
     release v=12.04,o=Ubuntu,a=precise-security,n=precise,l=Ubuntu,c=multiverse
     origin security.ubuntu.com
 500 http://security.ubuntu.com/ubuntu/ precise-security/restricted i386 Packages
     release v=12.04,o=Ubuntu,a=precise-security,n=precise,l=Ubuntu,c=restricted
     origin security.ubuntu.com
 500 http://security.ubuntu.com/ubuntu/ precise-security/universe i386 Packages
     release v=12.04,o=Ubuntu,a=precise-security,n=precise,l=Ubuntu,c=universe
     origin security.ubuntu.com
 500 http://security.ubuntu.com/ubuntu/ precise-security/main i386 Packages
     release v=12.04,o=Ubuntu,a=precise-security,n=precise,l=Ubuntu,c=main
     origin security.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise-backports/restricted Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise-backports/multiverse Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise-backports/main Translation-en
 100 http://us.archive.ubuntu.com/ubuntu/ precise-backports/multiverse i386 Packages
     release v=12.04,o=Ubuntu,a=precise-backports,n=precise,l=Ubuntu,c=multiverse
     origin us.archive.ubuntu.com
 100 http://us.archive.ubuntu.com/ubuntu/ precise-backports/restricted i386 Packages
     release v=12.04,o=Ubuntu,a=precise-backports,n=precise,l=Ubuntu,c=restricted
     origin us.archive.ubuntu.com
 100 http://us.archive.ubuntu.com/ubuntu/ precise-backports/universe i386 Packages
     release v=12.04,o=Ubuntu,a=precise-backports,n=precise,l=Ubuntu,c=universe
     origin us.archive.ubuntu.com
 100 http://us.archive.ubuntu.com/ubuntu/ precise-backports/main i386 Packages
     release v=12.04,o=Ubuntu,a=precise-backports,n=precise,l=Ubuntu,c=main
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/restricted Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/multiverse Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/main Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/multiverse i386 Packages
     release v=12.04,o=Ubuntu,a=precise-updates,n=precise,l=Ubuntu,c=multiverse
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/restricted i386 Packages
     release v=12.04,o=Ubuntu,a=precise-updates,n=precise,l=Ubuntu,c=restricted
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/universe i386 Packages
     release v=12.04,o=Ubuntu,a=precise-updates,n=precise,l=Ubuntu,c=universe
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/main i386 Packages
     release v=12.04,o=Ubuntu,a=precise-updates,n=precise,l=Ubuntu,c=main
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise/restricted Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise/multiverse Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise/main Translation-en
 500 http://us.archive.ubuntu.com/ubuntu/ precise/multiverse i386 Packages
     release v=12.04,o=Ubuntu,a=precise,n=precise,l=Ubuntu,c=multiverse
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise/restricted i386 Packages
     release v=12.04,o=Ubuntu,a=precise,n=precise,l=Ubuntu,c=restricted
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise/universe i386 Packages
     release v=12.04,o=Ubuntu,a=precise,n=precise,l=Ubuntu,c=universe
     origin us.archive.ubuntu.com
 500 http://us.archive.ubuntu.com/ubuntu/ precise/main i386 Packages
     release v=12.04,o=Ubuntu,a=precise,n=precise,l=Ubuntu,c=main
     origin us.archive.ubuntu.com
Pinned packages:
kanon@kanon-Vostro-1500:/etc/modprobe.d$ apt-cache policy gtk2-engines-pixbuf
gtk2-engines-pixbuf:
  Installed: (none)
  Candidate: 2.24.10-0ubuntu6.1
  Version table:
     2.24.10-0ubuntu6.1 0
        500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/universe i386 Packages
     2.24.10-0ubuntu6 0
        500 http://us.archive.ubuntu.com/ubuntu/ precise/universe i386 Packages
kanon@kanon-Vostro-1500:/etc/modprobe.d$ apt-get --simulate install gtk2-engines-pixbuf python-mlt python-support
NOTE: This is only a simulation!
      apt-get needs root privileges for real execution.
      Keep also in mind that locking is deactivated,
      so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree
Reading state information... Done
python-mlt is already the newest version.
The following NEW packages will be installed:
  gtk2-engines-pixbuf python-support
0 upgraded, 2 newly installed, 0 to remove and 5 not upgraded.
Inst gtk2-engines-pixbuf (2.24.10-0ubuntu6.1 Ubuntu:12.04/precise-updates [i386])
Inst python-support (1.0.14ubuntu2 Ubuntu:12.04/precise [all])
Conf gtk2-engines-pixbuf (2.24.10-0ubuntu6.1 Ubuntu:12.04/precise-updates [i386])
Conf python-support (1.0.14ubuntu2 Ubuntu:12.04/precise [all])

Please provide also the output of the commands

apt-cache policy python-mlt python-mlt5 python-mlt3 python-mlt2
apt-get --simulate dist-upgrade

kanon@kanon-Vostro-1500:~$ apt-cache policy python-mlt python-mlt5 python-mlt3 python-mlt2
python-mlt:
  Installed: 0.9.0-3~sunab~precise1
  Candidate: 0.9.0-3~sunab~precise1
  Version table:
 *** 0.9.0-3~sunab~precise1 0
        500 http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu/ precise/main i386 Packages
        100 /var/lib/dpkg/status
python-mlt5:
  Installed: (none)
  Candidate: (none)
  Version table:
python-mlt3:
  Installed: (none)
  Candidate: 0.7.6+git20120204-2
  Version table:
     0.7.6+git20120204-2 0
        500 http://us.archive.ubuntu.com/ubuntu/ precise/universe i386 Packages
python-mlt2:
  Installed: (none)
  Candidate: (none)
  Version table:
kanon@kanon-Vostro-1500:~$ apt-get --simulate dist-upgrade
NOTE: This is only a simulation!
      apt-get needs root privileges for real execution.
      Keep also in mind that locking is deactivated,
      so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages will be upgraded:
  firefox firefox-locale-en wine-compholio wine-staging wine-staging-i386
5 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Inst wine-staging [1.7.39~ubuntu12.04.1] (1.7.40~ubuntu12.04.1 compholio:12.04/precise [i386]) []
Inst wine-staging-i386 [1.7.39~ubuntu12.04.1] (1.7.40~ubuntu12.04.1 compholio:12.04/precise [i386])
Inst firefox [37.0+build2-0ubuntu0.12.04.1] (37.0.1+build1-0ubuntu0.12.04.1 Ubuntu:12.04/precise-updates [i386])
Inst firefox-locale-en [37.0+build2-0ubuntu0.12.04.1] (37.0.1+build1-0ubuntu0.12.04.1 Ubuntu:12.04/precise-updates [i386])
Inst wine-compholio [1.7.39~ubuntu12.04.1] (1.7.40~ubuntu12.04.1 compholio:12.04/precise [i386])
Conf wine-staging-i386 (1.7.40~ubuntu12.04.1 compholio:12.04/precise [i386])
Conf wine-staging (1.7.40~ubuntu12.04.1 compholio:12.04/precise [i386])
Conf firefox (37.0.1+build1-0ubuntu0.12.04.1 Ubuntu:12.04/precise-updates [i386])
Conf firefox-locale-en (37.0.1+build1-0ubuntu0.12.04.1 Ubuntu:12.04/precise-updates [i386])
Conf wine-compholio (1.7.40~ubuntu12.04.1 compholio:12.04/precise [i386])

For me it looks as if all dependencies can be fulfilled.

Try again with the command

sudo apt-get install openshot

and if that fails again with "unmet dependencies" messages, try

sudo apt-get install openshot gtk2-engines-pixbuf python-mlt3 python-support

and report the outcome.

Both these commands didn't work. Here's the output:

kanon@kanon-Vostro-1500:~$ sudo apt-get install openshot
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 openshot : Depends: python-mlt5 but it is not installable or
                     python-mlt3 but it is not going to be installed or
                     python-mlt2 but it is not installable
E: Unable to correct problems, you have held broken packages.
kanon@kanon-Vostro-1500:~$ sudo apt-get install openshot gtk2-engines-pixbuf python-mlt3 python-support
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 python-mlt3 : Depends: libmlt4 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

What is the output of

apt-cache policy libmlt4
apt-get --simulate install libmlt4

kanon@kanon-Vostro-1500:~$ apt-cache policy libmlt4
libmlt4:
  Installed: (none)
  Candidate: 0.7.6+git20120204-2
  Version table:
     0.7.6+git20120204-2 0
        500 http://us.archive.ubuntu.com/ubuntu/ precise/universe i386 Packages
kanon@kanon-Vostro-1500:~$ apt-get --simulate install libmlt4
NOTE: This is only a simulation!
      apt-get needs root privileges for real execution.
      Keep also in mind that locking is deactivated,
      so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libvidstab1.0 dvgrab libmovit2 swh-plugins kdenlive-data libepoxy0 libqjson0
  recordmydesktop
Use 'apt-get autoremove' to remove them.
The following packages will be REMOVED:
  kdenlive libmlt++3 libmlt6 melt python-mlt
The following NEW packages will be installed:
  libmlt4
0 upgraded, 1 newly installed, 5 to remove and 0 not upgraded.
Remv kdenlive [0.9.10-0ubuntu0~sunab~precise1]
Remv python-mlt [0.9.0-3~sunab~precise1]
Remv melt [0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1]
Remv libmlt++3 [0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1] [libmlt6:i386 ]
Remv libmlt6 [0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1]
Inst libmlt4 (0.7.6+git20120204-2 Ubuntu:12.04/precise [i386])
Conf libmlt4 (0.7.6+git20120204-2 Ubuntu:12.04/precise [i386])

Ok.

There seems to be a conflict between some packages, apparently the version of kdenlive has dependencies that are in conflict with the dependent packages for openshot.

The command

sudo apt-get install libmlt4 openshot

should be able to install openshot after removing kdenlive and dome additional packages.

It didn't work.

I did what you describe above, separating it into several apt-get calls: First, I uninstalled kdenlive. Then I installed libmlt4, which removed the other packages. All this went fine. Then, I tried to install openshot and got:

kanon@kanon-Vostro-1500:~$ sudo apt-get install openshot
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 openshot : Depends: python-mlt5 but it is not installable or
                     python-mlt3 but it is not going to be installed or
                     python-mlt2 but it is not installable
E: Unable to correct problems, you have held broken packages.

Here's the output of the other apt-get calls if you need those too:

kanon@kanon-Vostro-1500:~$ sudo apt-get remove kdenlive
[sudo] password for kanon:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  melt dvgrab swh-plugins kdenlive-data libqjson0 recordmydesktop
Use 'apt-get autoremove' to remove them.
The following packages will be REMOVED:
  kdenlive
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
After this operation, 4,789 kB disk space will be freed.
Do you want to continue [Y/n]?
(Reading database ... 745931 files and directories currently installed.)
Removing kdenlive ...
Processing triggers for man-db ...
Processing triggers for menu ...
Processing triggers for desktop-file-utils ...
Processing triggers for bamfdaemon ...
Rebuilding /usr/share/applications/bamf.index...
Processing triggers for gnome-menus ...
kanon@kanon-Vostro-1500:~$ sudo apt-get install libmlt4
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libvidstab1.0 dvgrab libmovit2 swh-plugins kdenlive-data libepoxy0 libqjson0
  recordmydesktop
Use 'apt-get autoremove' to remove them.
The following packages will be REMOVED:
  libmlt++3 libmlt6 melt python-mlt
The following NEW packages will be installed:
  libmlt4
0 upgraded, 1 newly installed, 4 to remove and 0 not upgraded.
Need to get 553 kB of archives.
After this operation, 840 kB disk space will be freed.
Do you want to continue [Y/n]?
Get:1 http://us.archive.ubuntu.com/ubuntu/ precise/universe libmlt4 i386 0.7.6+git20120204-2 [553 kB]
Fetched 553 kB in 6s (85.5 kB/s)
(Reading database ... 745917 files and directories currently installed.)
Removing python-mlt ...
Removing melt ...
Removing libmlt++3 ...
Removing libmlt6 ...
Processing triggers for man-db ...
Processing triggers for libc-bin ...
ldconfig deferred processing now taking place
Selecting previously unselected package libmlt4.
(Reading database ... 745869 files and directories currently installed.)
Unpacking libmlt4 (from .../libmlt4_0.7.6+git20120204-2_i386.deb) ...
Setting up libmlt4 (0.7.6+git20120204-2) ...
Processing triggers for libc-bin ...
ldconfig deferred processing now taking place
kanon@kanon-Vostro-1500:~$ sudo apt-get install openshot
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 openshot : Depends: python-mlt5 but it is not installable or
                     python-mlt3 but it is not going to be installed or
                     python-mlt2 but it is not installable
E: Unable to correct problems, you have held broken packages.

What is the output of

audo spt-get install python-mlt3 openshot

kanon@kanon-Vostro-1500:~$ sudo apt-get install python-mlt3 openshot
[sudo] password for kanon:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 openshot : Depends: melt but it is not going to be installed
 python-mlt3 : Depends: libmlt++3 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

What is the output of

apt-cache policy libmlt++3
apt-get --simulate install libmlt++3

kanon@kanon-Vostro-1500:~$ apt-cache policy libmlt++3
libmlt++3:
  Installed: (none)
  Candidate: 0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1
  Version table:
     0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1 0
        500 http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu/ precise/main i386 Packages
        100 /var/lib/dpkg/status
     0.7.6+git20120204-2 0
        500 http://us.archive.ubuntu.com/ubuntu/ precise/universe i386 Packages
kanon@kanon-Vostro-1500:~$ apt-get --simulate install libmlt++3
NOTE: This is only a simulation!
      apt-get needs root privileges for real execution.
      Keep also in mind that locking is deactivated,
      so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  dvgrab swh-plugins kdenlive-data libqjson0 recordmydesktop
Use 'apt-get autoremove' to remove them.
The following extra packages will be installed:
  libmlt6
The following packages will be REMOVED:
  libmlt4
The following NEW packages will be installed:
  libmlt++3 libmlt6
0 upgraded, 2 newly installed, 1 to remove and 15 not upgraded.
Remv libmlt4 [0.7.6+git20120204-2]
Inst libmlt6 (0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1 kdenlive-release:12.04/precise [i386]) []
Inst libmlt++3 (0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1 kdenlive-release:12.04/precise [i386])
Conf libmlt6 (0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1 kdenlive-release:12.04/precise [i386])
Conf libmlt++3 (0.9.3+git20140926.bbf724b6-0ubuntu0~sunab~precise1 kdenlive-release:12.04/precise [i386])
kanon@kanon-Vostro-1500:~$

That fixed it. Thanks!