Use OSError not IOError everywhere in CPython
Use OSError not IOError everywhere in CPython

F1000Research/khmer,Winterflower/khmer,Winterflower/khmer,Winterflower/khmer,ged-lab/khmer,souravsingh/khmer,ged-lab/khmer,souravsingh/khmer,F1000Research/khmer,F1000Research/khmer,ged-lab/khmer,souravsingh/khmer