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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 attrsignal(descriptor, signal_name, *, defer=False):
 """ Connect the decorated method or coroutine method to the addressed signal on a descriptor. :param descriptor: The descriptor to connect to. :type descriptor: :class:`Descriptor` subclass. :param signal_name: Attribute name of the signal to connect to :type signal_name: :class:`str` :param defer: Flag indicating whether deferred execution of the decorated method is desired; see below for details. :type defer: :class:`bool` The signal is discovered by accessing the attribute with the name `signal_name` on the :attr:`~Descriptor.value_type` of the `descriptor`. During instantiation of the service, the value of the descriptor is used to obtain the signal and then the decorated method is connected to the signal. If the signal is a :class:`.callbacks.Signal` and `defer` is false, the decorated object is connected using the default :attr:`~.callbacks.AdHocSignal.STRONG` mode. If the signal is a :class:`.callbacks.Signal` and `defer` is true and the decorated object is a coroutine function, the :attr:`~.callbacks.AdHocSignal.SPAWN_WITH_LOOP` mode with the default asyncio event loop is used. If the decorated object is not a coroutine function, :attr:`~.callbacks.AdHocSignal.ASYNC_WITH_LOOP` is used instead. If the signal is a :class:`.callbacks.SyncSignal`, `defer` must be false and the decorated object must be a coroutine function. .. versionadded:: 0.9 """

    def decorator(f):
        add_handler_spec(
            f,
            _attrsignal_spec(descriptor, signal_name, f, defer)
        )
        return f
    return decorator