code: def main():
      import matplotlib
  
      matplotlib.use("Agg")
  
      parser = ArgumentParser(
          description=DESCRIP,
          epilog=EPILOG,
          formatter_class=RawDescriptionHelpFormatter,
      )
      parser.add_argument(
          "filename", type=str, help="4D image filename"
      )
      parser.add_argument(
          "--out-path", type=str, help="path for output image files"
      )
      parser.add_argument(
          "--out-fname-label",
          type=str,
          help="mid part of output image filenames",
      )
      parser.add_argument(
          "--ncomponents",
          type=int,
          default=10,
          help="number of PCA components to write",
      )
      parser.add_argument(
          "--time-axis",
          type=str,
          default=-1,
          help="Image axis for time",
      )
      parser.add_argument(
          "--slice-axis",
          type=str,
          default=None,
          help="Image axis for slice",
      )
      # parse the command line
      args = parser.parse_args()
      nadc.diagnose(args)
  
label_desc: Use image node_id 1 for calling a global function with example usage: main() without return types