Fixed for Python 3

The print statements were not compatible with Python 3.  Also the
except statement at line 43 was in the old, Python 2 syntax.

Change-Id: I24d5b57a81ba9429c4770f2e8ad67d3012d604ca
Merge topic 'SIMPLEITK-582_UnableLoadDICOMSeriesByID' into next

b48bbea6 Fixed for Python 3