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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _make_window(window_dict):
 """ Creates a new class for that window and registers it at this module. """

    cls_name = '%sWindow' % camel_case(str(window_dict['name']))
    bases = (Window,)
    attrs = {
        '__module__': sys.modules[__name__],
        'name': str(window_dict['name']),
        'inv_type': str(window_dict['id']),
        'inv_data': window_dict,
    }

    # creates function-local index and size variables
    def make_slot_method(index, size=1):
        if size == 1:
            return lambda self: self.slots[index]
        else:
            return lambda self: self.slots[index:(index + size)]

    for slots in window_dict.get('slots', []):
        index = slots['index']
        size = slots.get('size', 1)
        attr_name = snake_case(str(slots['name']))
        attr_name += '_slot' if size == 1 else '_slots'
        slots_method = make_slot_method(index, size)
        slots_method.__name__ = attr_name
        attrs[attr_name] = property(slots_method)

    for i, prop_name in enumerate(window_dict.get('properties', [])):
        def make_prop_method(i):
            return lambda self: self.properties[i]
        prop_method = make_prop_method(i)
        prop_name = snake_case(str(prop_name))
        prop_method.__name__ = prop_name
        attrs[prop_name] = property(prop_method)

    cls = type(cls_name, bases, attrs)
    assert not hasattr(sys.modules[__name__], cls_name), \
        'Window "%s" already registered at %s' % (cls_name, __name__)
    setattr(sys.modules[__name__], cls_name, cls)
    return cls