code: def test_identity(self, xp):
      maxlen = 512
      x = xp.asarray(random(maxlen) + 1j * random(maxlen))
      xr = xp.asarray(random(maxlen))
      for i in range(1, maxlen):
          xp_assert_close(
              fft.ifft(fft.fft(x[0:i])), x[0:i], rtol=1e-9, atol=0
          )
          xp_assert_close(
              fft.irfft(fft.rfft(xr[0:i]), i),
              xr[0:i],
              rtol=1e-9,
              atol=0,
          )
  
imports: import queue
  import threading
  import multiprocessing
  import numpy
  import pytest
  from numpy.random import random
  from numpy.testing import assert_array_almost_equal, assert_allclose
  from pytest import raises
  import scipy.fft
  from scipy.conftest import array_api_compatible, skip_if_array_api_backend
  from scipy._lib._array_api import array_namespace, size, xp_assert_close, xp_assert_equal
label_desc: Use image node_id 1 for calling the TestFFT1D obj's underlying member method code with example usage: obj.test_identity(xp) without return types