code: def test_hash(self):
      v1 = DenseVector([0.0, 1.0, 0.0, 5.5])
      v2 = SparseVector(4, [(1, 1.0), (3, 5.5)])
      v3 = DenseVector([0.0, 1.0, 0.0, 5.5])
      v4 = SparseVector(4, [(1, 1.0), (3, 2.5)])
      self.assertEqual(hash(v1), hash(v2))
      self.assertEqual(hash(v1), hash(v3))
      self.assertEqual(hash(v2), hash(v3))
      self.assertFalse(hash(v1) == hash(v4))
      self.assertFalse(hash(v2) == hash(v4))
  
imports: import unittest
  import array
  from numpy import arange, array, array_equal, inf, ones, tile, zeros
  from pyspark.serializers import CPickleSerializer
  from pyspark.ml.linalg import DenseMatrix, DenseVector, MatrixUDT, SparseMatrix, SparseVector, Vector, VectorUDT, Vectors
  from pyspark.testing.mllibutils import MLlibTestCase
  from pyspark.sql import Row
  from pyspark.sql.functions import unwrap_udt
label_desc: Use image node_id 5 for calling the VectorTests obj's underlying member method code with example usage: obj.test_hash() without return types