[v1.6.8] ImportError - c:\python\32-bit\3.4\lib\importlib\_bootstrap.py:2224

OpenNumismat: 1.6.8
OS: Windows 10 (10.0.16299)
Python: 3.4.4 (32bit)
Qt: 5.5.1
Locale: en

Traceback (most recent call last):
File "d:\OpenNumismat\open-numismat\OpenNumismat\StatisticsView.py", line 526, in save
File "C:\Python34\lib\site-packages\matplotlib\figure.py", line 1814, in savefig
File "C:\Python34\lib\site-packages\matplotlib\backends\backend_qt5agg.py", line 172, in print_figure
File "C:\Python34\lib\site-packages\matplotlib\backend_bases.py", line 2162, in print_figure
File "C:\Python34\lib\site-packages\matplotlib\backend_bases.py", line 2097, in _get_output_canvas
File "C:\Python34\lib\site-packages\matplotlib\backend_bases.py", line 133, in get_registered_canvas_class
File "C:\Python34\lib\importlib\__init__.py", line 109, in import_module
File "c:\python\32-bit\3.4\lib\importlib\_bootstrap.py", line 2254, in _gcd_import
File "c:\python\32-bit\3.4\lib\importlib\_bootstrap.py", line 2237, in _find_and_load
File "c:\python\32-bit\3.4\lib\importlib\_bootstrap.py", line 2224, in _find_and_load_unlocked
ImportError: No module named 'matplotlib.backends.backend_ps'