code: def test_leave_free_mbs():
      preload_pytorch()
  
      delta = 10
      free_before = gpu_mem_get_free_mbs()
      assert free_before > delta, "have some free gpu memory"
  
      left = free_before - delta
      buf = gpu_mem_leave_free_mbs(left)
      assert buf is not None, f"able to allocate {delta} mem"
  
      free_after = gpu_mem_get_free_mbs()
      assert isclose(
          free_after, left, abs_tol=1
      ), f"allocated {delta}, before {free_before}, after {free_after}"
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_leave_free_mbs() without return types