code: def test_prefer_short_narrow(abcde):
      # See test_prefer_short_ancestor for a fail case.
      a, b, c, _, _ = abcde
      dsk = {
          (a, 0): 0,
          (b, 0): 0,
          (c, 0): 0,
          (c, 1): (f, (c, 0), (a, 0), (b, 0)),
          (a, 1): 1,
          (b, 1): 1,
          (c, 2): (f, (c, 1), (a, 1), (b, 1)),
      }
      o = order(dsk)
      assert o[(b, 0)] < o[(b, 1)]
      assert o[(b, 0)] < o[(c, 2)]
      assert o[(c, 1)] < o[(c, 2)]
  
imports: import pytest
  from flash.core.serve.dag.order import ndependencies, order
  from flash.core.serve.dag.task import get, get_deps
  from flash.core.serve.dag.utils_test import add, inc
  from flash.core.utilities.imports import _TOPIC_SERVE_AVAILABLE
label_desc: Use image node_id 21 for calling a global function with example usage: test_prefer_short_narrow(abcde) without return types