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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 dfs(args=None, properties=None, hadoop_conf_dir=None):
 """ Run the Hadoop file system shell. All arguments are passed to :func:`run_class`. """

    # run FsShell directly (avoids "hadoop dfs" deprecation)
    return run_class(
        "org.apache.hadoop.fs.FsShell", args, properties,
        hadoop_conf_dir=hadoop_conf_dir, keep_streams=True
    )