code: def _test_load_store_helper(self, xp, dtype, fft_func):
      fft = getattr(xp.fft, fft_func)
      load_code = _load_callback
      store_code = _store_callback
      if fft_func in ("fft", "ifft"):
          if dtype == np.complex64:
              load_types = ("x.x", "cufftComplex", "cufftCallbackLoadC")
              store_types = (
                  "x.y",
                  "cufftComplex",
                  "cufftCallbackStoreC",
              )
          else:
              load_types = (
                  "x.x",
                  "cufftDoubleComplex",
                  "cufftCallbackLoadZ",
              )
              store_types = (
                  "x.y",
                  "cufftDoubleComplex",
                  "cufftCallbackStoreZ",
              )
      elif fft_func == "rfft":
          if dtype == np.float32:
              load_types = ("x", "cufftReal", "cufftCallbackLoadR")
              store_types = (
                  "x.y",
                  "cufftComplex",
                  "cufftCallbackStoreC",
              )
          else:
              load_types = (
                  "x",
                  "cufftDoubleReal",
                  "cufftCallbackLoadD",
              )
              store_types = (
                  "x.y",
                  "cufftDoubleComplex",
                  "cufftCallbackStoreZ",
              )
      else:  # irfft
          if dtype == np.complex64:
              load_types = ("x.x", "cufftComplex", "cufftCallbackLoadC")
              store_types = ("x", "cufftReal", "cufftCallbackStoreR")
          else:
              load_types = (
                  "x.x",
                  "cufftDoubleComplex",
                  "cufftCallbackLoadZ",
              )
              store_types = (
                  "x",
                  "cufftDoubleReal",
                  "cufftCallbackStoreD",
              )
      cb_load = _set_load_cb(load_code, *load_types)
      cb_store = _set_store_cb(store_code, *store_types)
  
      a = testing.shaped_random(self.shape, xp, dtype)
      if xp is np:
          a.real *= 2.5
          out = fft(a, n=self.n, norm=self.norm)
          if fft_func != "irfft":
              out.imag /= 3.8
              if dtype in (np.float32, np.complex64):
                  out = out.astype(np.complex64)
          else:
              out /= 3.8
              if dtype in (np.float32, np.complex64):
                  out = out.astype(np.float32)
      else:
          with use_temporary_cache_dir():
              with xp.fft.config.set_cufft_callbacks(
                  cb_load=cb_load, cb_store=cb_store
              ):
                  out = fft(a, n=self.n, norm=self.norm)
  
      return out
  
imports: import contextlib
  import string
  import sys
  import tempfile
  from unittest import mock
  import numpy
  import pytest
  import cupy
  from cupy import testing
label_desc: Use image node_id 11 for calling the Test1dCallbacks obj's underlying member method code with example usage: obj._test_load_store_helper(xp, dtype, fft_func) and returns: out