Why am I getting "python:any (>= 2.7.1-0ubuntu2) but it is not installable" on Raspian Wheezy?

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The answer to this problem is quite simple (ok, it took me two days until I read the complete article http://wiki.ros.org/ROSberryPi/Instal... and found the correct hint):

Just befor section "2.3 Building the catkin Workspace" is a box with the following note:

Note: Rosdep may report that python-rosdep, python-catkin-pkg, python-rospkg, and python-rosdistro failed to install; however, you can ignore this error because they have already been installed with pip.

Me too, and I have no ':any' in that file, what's the fix is it to reinstall python?

On a brand new Raspian Wheezy I geht this:

The following packages have unmet dependencies:
python-rosdep : Depends: python:any (>= 2.7.1-0ubuntu2) but it is not installable
             Depends: python-catkin-pkg but it is not going to be installed
             Depends: python-rospkg (>= 1.0.34) but it is not going to be installed
             Depends: python-rosdistro (>= 0.4.0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
ERROR: the following rosdeps failed to install
apt: command [sudo -H apt-get install -y python-rospkg] failed
apt: command [sudo -H apt-get install -y python-catkin-pkg] failed
apt: command [sudo -H apt-get install -y python-rosdep] failed
apt: Failed to detect successful installation of [python-rospkg]
apt: Failed to detect successful installation of [python-catkin-pkg]
apt: Failed to detect successful installation of [python-

The unmet dependencies can't be ignored, right?