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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 tracking_event_post(node_id):
 """Enqueue a TrackingEvent worker for the specified Node. """

    details = request_parameter(parameter="details", optional=True)
    if details:
        details = loads(details)

    # check the node exists
    node = models.Node.query.get(node_id)
    if node is None:
        return error_response(error_type="/info POST, node does not exist")

    db.logger.debug(
        "rq: Queueing %s with for node: %s for worker_function",
        "TrackingEvent",
        node_id,
    )
    q.enqueue(
        worker_function, "TrackingEvent", None, None, node_id=node_id, details=details
    )

    return success_response(details=details)