code: def test_first_genfname():
      first = fsl.FIRST()
      first.inputs.out_file = "segment.nii"
      first.inputs.output_type = "NIFTI_GZ"
  
      value = first._gen_fname(basename="original_segmentations")
      expected_value = os.path.abspath(
          "segment_all_fast_origsegs.nii.gz"
      )
      assert value == expected_value
      first.inputs.method = "none"
      value = first._gen_fname(basename="original_segmentations")
      expected_value = os.path.abspath(
          "segment_all_none_origsegs.nii.gz"
      )
      assert value == expected_value
      first.inputs.method = "auto"
      first.inputs.list_of_specific_structures = ["L_Hipp", "R_Hipp"]
      value = first._gen_fname(basename="original_segmentations")
      expected_value = os.path.abspath(
          "segment_all_none_origsegs.nii.gz"
      )
      assert value == expected_value
  
imports: import os
  from copy import deepcopy
  import pytest
  import pdb
  from nipype.utils.filemanip import split_filename, ensure_list
  from ..None import preprocess
  from nipype.interfaces.fsl import Info
  from nipype.interfaces.base import File, TraitError, Undefined, isdefined
  from nipype.interfaces.fsl import no_fsl
label_desc: Use image node_id 15 for calling a global function with example usage: test_first_genfname() without return types