code: def setUp(self):
      if self.stream == "null":
          self.stream = cupy.cuda.Stream.null
      elif self.stream == "new":
          self.stream = cupy.cuda.Stream()
      elif self.stream == "ptds":
          self.stream = cupy.cuda.Stream.ptds
  
imports: import unittest
  import pytest
  from cupy_backends.cuda import stream
  import cupy
  from cupy import _core
  from cupy import testing
label_desc: Use image node_id 1 for calling the TestCUDAArrayInterfaceStream obj's underlying member method code with example usage: obj.setUp() without return types