code: def test_fft_forward_backward(
      seed, ctx, func_name, batch_dims, signal_ndim, dims, normalized
  ):
      if func_name == "IFFT":
          pytest.skip("Not implemented in CPU.")
  
      from nbla_test_utils import (
          function_tester,
          convert_to_float2_array,
          convert_to_complex_array,
      )
  
      rng = np.random.RandomState(seed)
      shape = batch_dims + dims
      x_data_complex = rng.rand(*shape) + 1j * rng.rand(*shape)
      x_data = convert_to_float2_array(x_data_complex)
      inputs = [x_data]
      func_args = [signal_ndim, normalized]
      function_tester(
          rng,
          F.ifft,
          ref_ifft,
          inputs,
          func_args=func_args,
          atol_f=1e-4,
          atol_b=1e-4,
          backward=[True],
          ctx=ctx,
          func_name=func_name,
          ref_grad=ref_grad_ifft,
          disable_half_test=True,
      )
  
file_path: nnabla/python/test/function/test_ifft.py
imports: import pytest
  import numpy
  import sys
  import nnabla.functions
  from nbla_test_utils import list_context
label_desc: Use image node_id 3 for calling a global function with example usage: test_fft_forward_backward(seed, ctx, func_name, batch_dims, signal_ndim, dims, normalized) without return types