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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 build_message_key(self, message) -> str: """Given a message, return its globally-unique key. Parameters: message(Message) Returns: str """

        message_key = "%(namespace)s:%(queue_name)s:%(actor_name)s:%(message_id)s" % {
            "namespace": self.namespace,
            "queue_name": q_name(message.queue_name),
            "actor_name": message.actor_name,
            "message_id": message.message_id,
        }
        return hashlib.md5(message_key.encode("utf-8")).hexdigest()