def test_original_item_unaffected(self):
        item = {
            'foo': 'bar',
            'baz': [1, 2, 3]
        }
        get_signed_item(item, PUBLIC_KEY, PRIVATE_KEY)
        self.assertNotIn('_p4p2p', item)
        self.assertEqual(2, len(item))
        self.assertIn('foo', item)
        self.assertIn('baz', item)
        self.assertEqual(item['foo'], 'bar')
        self.assertEqual(item['baz'], [1, 2, 3])
Ensure the item (dict) passed into the function is not changed.
dataset/ETHPy150Open ntoll/p4p2p/test/dht/test_crypto.py/TestGetSignedItem.test_original_item_unaffected