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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 call(self, event, data=None, namespace=None, timeout=60):
 """Emit a custom event to a client and wait for the response. :param event: The event name. It can be any string. The event names ``'connect'``, ``'message'`` and ``'disconnect'`` are reserved and should not be used. :param data: The data to send to the client or clients. Data can be of type ``str``, ``bytes``, ``list`` or ``dict``. If a ``list`` or ``dict``, the data will be serialized as JSON. :param namespace: The Socket.IO namespace for the event. If this argument is omitted the event is emitted to the default namespace. :param timeout: The waiting timeout. If the timeout is reached before the client acknowledges the event, then a ``TimeoutError`` exception is raised. """

        callback_event = self.eio.create_event()
        callback_args = []

        def event_callback(*args):
            callback_args.append(args)
            callback_event.set()

        self.emit(event, data=data, namespace=namespace,
                  callback=event_callback)
        if not callback_event.wait(timeout=timeout):
            raise exceptions.TimeoutError()
        return callback_args[0] if len(callback_args[0]) > 1 \
            else callback_args[0][0] if len(callback_args[0]) == 1 \
                else None