code: def setup_module():
      global DATA
  
      DATA["empty_tck_fname"] = pjoin(data_path, "empty.tck")
      DATA["no_magic_number_tck_fname"] = pjoin(
          data_path, "no_magic_number.tck"
      )
      DATA["no_header_end_tck_fname"] = pjoin(
          data_path, "no_header_end.tck"
      )
      DATA["no_header_end_eof_tck_fname"] = pjoin(
          data_path, "no_header_end_eof.tck"
      )
      # simple.tck contains only streamlines
      DATA["simple_tck_fname"] = pjoin(data_path, "simple.tck")
      DATA["simple_tck_big_endian_fname"] = pjoin(
          data_path, "simple_big_endian.tck"
      )
      # standard.tck contains only streamlines
      DATA["standard_tck_fname"] = pjoin(data_path, "standard.tck")
      DATA["matlab_nan_tck_fname"] = pjoin(data_path, "matlab_nan.tck")
      DATA["multiline_header_fname"] = pjoin(
          data_path, "multiline_header_field.tck"
      )
  
      DATA["streamlines"] = [
          np.arange(1 * 3, dtype="f4").reshape((1, 3)),
          np.arange(2 * 3, dtype="f4").reshape((2, 3)),
          np.arange(5 * 3, dtype="f4").reshape((5, 3)),
      ]
  
      DATA["empty_tractogram"] = Tractogram(affine_to_rasmm=np.eye(4))
      DATA["simple_tractogram"] = Tractogram(
          DATA["streamlines"], affine_to_rasmm=np.eye(4)
      )
  
imports: import os
  import unittest
  from io import BytesIO
  from os.path import join
  import numpy
  import pytest
  from numpy.testing import assert_array_equal
  from ...testing import data_path, error_warnings
  from ..None import tck
  from ..array_sequence import ArraySequence
  from ..tck import TckFile
  from ..tractogram import Tractogram
  from ..tractogram_file import DataError, HeaderError, HeaderWarning
  from .test_tractogram import assert_tractogram_equal
label_desc: Use image node_id 1 for calling a global function with example usage: setup_module() without return types