def METHOD_NAME(self, descriptor: BleakGATTDescriptor):
    """Add a :py:class:`~BleakGATTDescriptor` to the service collection.
    Should not be used by end user, but rather by `bleak` itself.
    """
    if descriptor.handle not in self.__descriptors:
        self.__descriptors[descriptor.handle] = descriptor
        self.__characteristics[descriptor.characteristic_handle].METHOD_NAME(
            descriptor
        )
    else:
        logger.error(
            "The descriptor '%s' is already present in this BleakGATTServiceCollection!",
            descriptor.handle,
        )