code: def test_storage_issue(self):
      engine1 = Engine(100)
      engine2 = Engine(100)
  
      for k in range(1000):
          x = numpy.random.randn(100)
          x_data = "data"
          engine1.store_vector(x, x_data)
  
      # Each engine should have its own default storage
      self.assertEqual(len(engine2.storage.buckets), 0)
  
imports: import itertools
  import unittest
  import numpy
  import scipy
  from future.builtins import range
  from nearpy import Engine
  from nearpy.utils.utils import unitvec
  from nearpy.hashes import UniBucket
label_desc: Use image node_id 2 for calling the TestEngine obj's underlying member method code with example usage: obj.test_storage_issue() without return types