rosdep has unmet dependencies

Question

My synaptic manager gives me an error saying that python-rosdep is broken in my system. So I did the following: Edit->Fix broken packages->Apply. But I get an error:

 E: /var/cache/apt/archives/python-catkin-pkg-modules_0.4.10-1_all.deb: subprocess dpkg-deb --control returned error exit status 2

E: /var/cache/apt/archives/python-catkin-pkg_0.4.10-100_all.deb: subprocess dpkg-deb --control returned error exit status 2

E: /var/cache/apt/archives/python-rosdistro-modules_0.7.2-1_all.deb: subprocess dpkg-deb --control returned error exit status 2

E: /var/cache/apt/archives/python-rosdistro_0.7.2-100_all.deb: subprocess dpkg-deb --control returned error exit status 2

W: Ignoring Provides line with DepCompareOp for package gdb-minimal
W: Ignoring Provides line with DepCompareOp for package gdb-minimal

If I run sudo apt-get -f install, that too gives me errors

dpkg-deb: error: archive '/var/cache/apt/archives/python-catkin-pkg-modules_0.4.10-1_all.deb' has premature member 'control.tar.xz' before 'control.tar.gz', giving up

dpkg: error processing archive /var/cache/apt/archives/python-catkin-pkg-modules_0.4.10-1_all.deb (--unpack):

subprocess dpkg-deb --control returned error exit status 2

dpkg-deb: error: archive '/var/cache/apt/archives/python-catkin-pkg_0.4.10-100_all.deb' has premature member 'control.tar.xz' before 'control.tar.gz', giving up

dpkg: error processing archive /var/cache/apt/archives/python-catkin-pkg_0.4.10-100_all.deb (--unpack):

subprocess dpkg-deb --control returned error exit status 2

dpkg-deb: error: archive '/var/cache/apt/archives/python-rosdistro-modules_0.7.2-1_all.deb' has premature member 'control.tar.xz' before 'control.tar.gz', giving up

dpkg: error processing archive /var/cache/apt/archives/python-rosdistro-modules_0.7.2-1_all.deb (--unpack):

subprocess dpkg-deb --control returned error exit status 2

dpkg-deb: error: archive '/var/cache/apt/archives/python-rosdistro_0.7.2-100_all.deb' has premature member 'control.tar.xz' before 'control.tar.gz', giving up

dpkg: error processing archive /var/cache/apt/archives/python-rosdistro_0.7.2-100_all.deb (--unpack):
subprocess dpkg-deb --control returned error exit status 2

No apport report written because MaxReports is reached already

Errors were encountered while processing:

/var/cache/apt/archives/python-catkin-pkg-modules_0.4.10-1_all.deb

/var/cache/apt/archives/python-catkin-pkg_0.4.10-100_all.deb

/var/cache/apt/archives/python-rosdistro-modules_0.7.2-1_all.deb

/var/cache/apt/archives/python-rosdistro_0.7.2-100_all.deb

E: Sub-process /usr/bin/dpkg returned an error code (1)

Because of this problem I am not able to install anything via apt-get because of the error:

the following packages have unmet dependencies: 
python-rosdep : Depends: python-catkin-pkg (>= 0.4.0) but 0.3.9-100 is to be installed`. 
Depends: python-rosdistro (>= 0.7.0) but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

Also, the output of apt-cache policy python-rosdep python-catkin-pkg is

python-rosdep:
Installed: 0.15.0-1
Candidate: 0.15.0-1
Version table:
*** 0.15.0-1 0
500 http://packages.ros.org/ros/ubuntu/ trusty/main amd64 Packages
    100 /var/lib/dpkg/status

python-catkin-pkg:
Installed: 0.3.9-100
Candidate: 0.4.10-100
Version table:
0.4.10-100 0
500 http://packages.ros.org/ros/ubuntu/ trusty/main amd64 Packages
*** 0.3.9-100 0
100 /var/lib/dpkg/status

Can someone help me solve this problem? Thanks