proxy_property.py

def __getattr__(self, name):
    # _children is a list of strings referring to properties in the wrapper object.
    for child in self._children:
        child = getattr(self, child)
        if hasattr(child, name):
	    return getattr(child, name)

    return AttributeError("No attribute '%s' in any children of %s" % (name, self))