def get_num_nodes(properties=None, hadoop_conf_dir=None, offline=False):
    """
    Get the number of task trackers in the Hadoop cluster.

    All arguments are passed to :func:`get_task_trackers`.
    """
    return len(get_task_trackers(properties, hadoop_conf_dir, offline))
Get the number of task trackers in the Hadoop cluster.

    All arguments are passed to :func:`get_task_trackers`.