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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 consume(self, callback, bindings=None, queues=None, exchanges=None):
 """ Consume messages from a message queue. Simply define a callable to be used as the callback when messages are delivered and specify the queue bindings. This call blocks. The callback signature should accept a single positional argument which is an instance of a :class:`Message` (or a sub-class of it). Args: callback (callable):
 The callable to pass the message to when one arrives. bindings (list of dict):
 A list of dictionaries describing bindings for queues. Refer to the :ref:`conf-bindings` configuration documentation for the format. queues (dict):
 A dictionary of queues to ensure exist. Refer to the :ref:`conf-queues` configuration documentation for the format. exchanges (dict):
 A dictionary of exchanges to ensure exist. Refer to the :ref:`conf-exchanges` configuration documentation for the format. Raises: HaltConsumer: Raised when the consumer halts. ValueError: If the callback isn't a callable object or a class with __call__ defined. """

        self._bindings = bindings or config.conf["bindings"]
        self._queues = queues or config.conf["queues"]
        self._exchanges = exchanges or config.conf["exchanges"]

        # If the callback is a class, create an instance of it first
        if inspect.isclass(callback):
            cb_obj = callback()
            if not callable(cb_obj):
                raise ValueError(
                    "Callback must be a class that implements __call__"
                    " or a function."
                )
            self._consumer_callback = cb_obj
        elif callable(callback):
            self._consumer_callback = callback
        else:
            raise ValueError(
                "Callback must be a class that implements __call__" " or a function."
            )
        self._running = True
        self.connect()
        self._connection.ioloop.start()