Fix resize_coordinate_window for python 3

[gregvonkuster]

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[mvdbeek]

Can you also use sys.exit(msg) on line 13 ? I suspect otherwise msg would need to be bytestring.

[gregvonkuster]

Sure, thanks @mvdbeek for pointing this out. I'm still getting familiar with some of these Python 3 twists - the sys.exit([arg]) description here https://docs.python.org/3/library/sys.html, states that integers are ok, so I left it alone. However, it also states that anything except an integer or None is printed to stderr and the exit code is set to 1. So should I also delete line 12 as part of this fix?

[mvdbeek]

Yes, that's more concise and that way we don't need to care about how we write to sys.stderr.

[gregvonkuster]

Done - thanks! ;)