code: def test_generic():
      s1 = Stream.source(["hello", "my", "name", "is"], dtype="string")
      s2 = Stream.source([1, 2, 3, 4, 5, 6])
  
      g1 = s1.apply(lambda x: x[0]).rename("g1")
      g2 = s2.lag().rename("g2")
  
      feed = DataFeed([g1, g2])
      feed.compile()
  
      feed.next()
      assert feed.next() == {"g1": "m", "g2": 1}
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_generic() without return types