Don't try closing dictionary file if it isn't open.
Don't try closing dictionary file if it isn't open.

The finally block is called when exiting on a 'return', so if there's an
IOError because the file doesn't exist, we tried to close the nonexistent file.
pierrelb/RMG-Py,comocheng/RMG-Py,faribas/RMG-Py,enochd/RMG-Py,chatelak/RMG-Py,KEHANG/RMG-Py,chatelak/RMG-Py,nyee/RMG-Py,nyee/RMG-Py,pierrelb/RMG-Py,KEHANG/RMG-Py,nickvandewiele/RMG-Py,comocheng/RMG-Py,faribas/RMG-Py,enochd/RMG-Py,nickvandewiele/RMG-Py