AttributeError on OSX 10.9.4 and Python 3.4.1

[crolfe]

I get the following error when I try to run toga-demo using OSX 10.9.4 and Python 3.4 (no issues with Python 2.7.5):

(env)185:test colin$ toga-demo
Traceback (most recent call last):
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/platform/cocoa/libs/objc.py", line 841, in has_property
return self.properties[name]
KeyError: b'initWithContentsOfFile_'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/Users/colin/Programming/python/test/env/bin/toga-demo", line 7, in
from toga_demo.main import main
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga_demo/main.py", line 8, in
import toga
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/init.py", line 80, in
from .platform.cocoa.app import *
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/platform/cocoa/app.py", line 7, in
from .widgets import Icon, TIBERIUS_ICON
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/platform/cocoa/widgets/init.py", line 5, in
from .icon import *
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/platform/cocoa/widgets/icon.py", line 32, in
TIBERIUS_ICON = Icon('tiberius.icns', system=True)
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/platform/cocoa/widgets/icon.py", line 18, in init
self.impl = NSImage.alloc().initWithContentsOfFile(get_NSString(filename))
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/platform/cocoa/libs/objc.py", line 936, in getattr
if self.objc_class.has_property(name):
File "/Users/colin/Programming/python/test/env/lib/python3.4/site-packages/toga/platform/cocoa/libs/objc.py", line 843, in has_property
selector = get_selector('set' + name[0].upper() + name[1:] + ':')
AttributeError: 'int' object has no attribute 'upper'

[freakboy3742]

This was an issue in the 0.1.0 of toga; it's subsequently been fixed. If you install from master, you should be able to run toga-demo under Py3.