code: def test_ctypes(self):
      bit_generator = self.bit_generator(*self.data1["seed"])
      ctypes_interface = bit_generator.ctypes
      assert isinstance(ctypes_interface, interface)
      other_ctypes_interface = bit_generator.ctypes
      assert other_ctypes_interface is ctypes_interface
  
imports: import os
  from os.path import join
  import sys
  import numpy
  from numpy.testing import assert_equal, assert_allclose, assert_array_equal, assert_raises
  import pytest
  from numpy.random import Generator, MT19937, PCG64, PCG64DXSM, Philox, RandomState, SeedSequence, SFC64, default_rng
  from numpy.random._common import interface
label_desc: Use image node_id 17 for calling the Base obj's underlying member method code with example usage: obj.test_ctypes() without return types