python3 tkinter issue on Testing and Jessie

I have the same issue either upgrading to 'Testing' or to 'Jessie'

I'm using the latest version of Raspian installed with the latest Noobs.

I change the sources list to:

deb http://mirrordirector.raspbian.org/raspbian/ jessie main contrib non-free rpi

or

deb http://mirrordirector.raspbian.org/raspbian/ testing main contrib non-free rpi

and do the apt-get update, apt-get upgrade and apt-get dist-upgrade

Just a note here to say that during upgrades it brings up the option to keep config files as are or copy new ones. I choose the default which is keep default.

From the command line I enter:

python3

then

import tkinter

I get the following error:

pi@raspberrypi ~ $ python3
Python 3.4.1 (default, Aug 1 2014, 10:02:51)
[GCC 4.9.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import tkinter
Traceback (most recent call last):
File "/usr/lib/python3.4/tkinter/__init__.py", line 39, in <module>
import _tkinter
ImportError: libBLT.2.4.so.8.6: cannot open shared object file: No such file or directory

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python3.4/tkinter/__init__.py", line 41, in <module>
raise ImportError(str(msg) + ', please install the python3-tk package')
ImportError: libBLT.2.4.so.8.6: cannot open shared object file: No such file or directory, please install the python3-tk package

Please let me know if you need any further information

Thanks

Peter Jones