code: def test_item_vector_after_save():
      # Issue #279
      a = AnnoyIndex(3, "angular")
      a.verbose(True)
      a.add_item(1, [1, 0, 0])
      a.add_item(2, [0, 1, 0])
      a.add_item(3, [0, 0, 1])
      a.build(-1)
      assert a.get_n_items() == 4
      assert a.get_item_vector(3) == [0, 0, 1]
      assert set(a.get_nns_by_item(1, 999)) == set([1, 2, 3])
      a.save("something.annoy")
      assert a.get_n_items() == 4
      assert a.get_item_vector(3) == [0, 0, 1]
      assert set(a.get_nns_by_item(1, 999)) == set([1, 2, 3])
  
imports: import os
  import random
  import pytest
  from annoy import AnnoyIndex
label_desc: Use image node_id 14 for calling a global function with example usage: test_item_vector_after_save() without return types