import gobject

class Parent(gobject.GObject):

    __gtype_name__ = 'TestParent'

    def __init__(self, **kwargs):
        gobject.GObject.__init__(self, **kwargs)

    def get_mec(self):
        return 'mec'
    mec = gobject.property(type=str, getter=get_mec)

class Child(Parent):

    __gtype_name__ = 'TestChild'

    def __init__(self, **kwargs):
        gobject.GObject.__init__(self, **kwargs)

    def get_mac(self):
        return 'mac'
    mac = gobject.property(type=str, getter=get_mac)

"""
Traceback (most recent call last):
  File "/home/tomeu/Desktop/test_new_properties.py", line 14, in <module>
    class Child(Parent):
  File "/var/lib/python-support/python2.5/gtk-2.0/gobject/__init__.py", line 40, in __init__
    cls._install_properties()
  File "/var/lib/python-support/python2.5/gtk-2.0/gobject/__init__.py", line 68, in _install_properties
    " or getter. This is not allowed" % (cls,))
TypeError: GObject subclass <class '__main__.Child'> defines do_get/set_property and it also uses a property which a custom setter or getter. This is not allowed
"""

