code: def test_create_read_graph():
      m = te.var("m")
      l = te.var("l")
      A = te.placeholder((m, l), name="A")
      A1 = te.compute((m, l), lambda i, j: A[i, j])
      A2 = te.compute((m, l), lambda i, j: A1[i, j] + 3)
  
      g = tvm.te.schedule.CreateReadGraph([A2.op])
  
      assert g[A2.op][0] == A1
      assert g[A1.op][0] == A
      post_order = tvm.te.schedule.PostDFSOrder([A2.op], g)
      assert post_order[0] == A.op
      assert post_order[1] == A1.op
  
imports: import tvm
  from tvm import te
label_desc: Use image node_id 3 for calling a global function with example usage: test_create_read_graph() without return types