new_contents: # Yielding from stopped generator is ok and results in None
  
  def gen():
      return 1
      # This yield is just to make this a generator
      yield
  
  f = gen()
  
  def run():
      print((yield from f))
      print((yield from f))
      print((yield from f))
  
  try:
      next(run())
  except StopIteration:
      print("StopIteration")
  
subject: Add testcase for yielding from a stopped generator.