code: def update():
      global ptr
      if next(iterations_counter) > args.iterations:
          timer.stop()
          app.quit()
          return None
      for i in range(nPlots):
          curves[i].setData(data[(ptr + i) % data.shape[0]])
  
      ptr += nPlots
      framecnt.update()
  
imports: import argparse
  import itertools
  import numpy
  from utils import FrameCounter
  import pyqtgraph
  from pyqtgraph.Qt import QtCore
label_desc: Use image node_id 1 for calling a global function with example usage: update() and returns: None