code: def data_gen():
      for cnt in itertools.count():
          t = cnt / 10
          yield t, np.sin(2 * np.pi * t) * np.exp(-t / 10.0)
  
imports: import itertools
  import matplotlib.pyplot
  import numpy
  import matplotlib.animation
label_desc: Use image node_id 1 for calling a global function with example usage: data_gen() without return types