code: def setup_module():
      global DATA
      DATA["rng"] = np.random.RandomState(1234)
  
      DATA["streamlines"] = []
      DATA["fa"] = []
      DATA["colors"] = []
      DATA["mean_curvature"] = []
      DATA["mean_torsion"] = []
      DATA["mean_colors"] = []
      for nb_points in [1, 2, 5]:
          data = make_dummy_streamline(nb_points)
          streamline, data_per_point, data_for_streamline = data
          DATA["streamlines"].append(streamline)
          DATA["fa"].append(data_per_point["fa"])
          DATA["colors"].append(data_per_point["colors"])
          DATA["mean_curvature"].append(
              data_for_streamline["mean_curvature"]
          )
          DATA["mean_torsion"].append(
              data_for_streamline["mean_torsion"]
          )
          DATA["mean_colors"].append(data_for_streamline["mean_colors"])
  
      DATA["data_per_point"] = {
          "colors": DATA["colors"],
          "fa": DATA["fa"],
      }
      DATA["data_per_streamline"] = {
          "mean_curvature": DATA["mean_curvature"],
          "mean_torsion": DATA["mean_torsion"],
          "mean_colors": DATA["mean_colors"],
      }
  
      DATA["empty_tractogram"] = Tractogram(affine_to_rasmm=np.eye(4))
      DATA["simple_tractogram"] = Tractogram(
          DATA["streamlines"], affine_to_rasmm=np.eye(4)
      )
      DATA["tractogram"] = Tractogram(
          DATA["streamlines"],
          DATA["data_per_streamline"],
          DATA["data_per_point"],
          affine_to_rasmm=np.eye(4),
      )
  
      DATA["streamlines_func"] = lambda: (
          e for e in DATA["streamlines"]
      )
      DATA["data_per_point_func"] = {
          "colors": lambda: (e for e in DATA["colors"]),
          "fa": lambda: (e for e in DATA["fa"]),
      }
      DATA["data_per_streamline_func"] = {
          "mean_curvature": lambda: (e for e in DATA["mean_curvature"]),
          "mean_torsion": lambda: (e for e in DATA["mean_torsion"]),
          "mean_colors": lambda: (e for e in DATA["mean_colors"]),
      }
  
      DATA["lazy_tractogram"] = LazyTractogram(
          DATA["streamlines_func"],
          DATA["data_per_streamline_func"],
          DATA["data_per_point_func"],
          affine_to_rasmm=np.eye(4),
      )
  
imports: import copy
  import operator
  import sys
  import unittest
  import warnings
  from collections import defaultdict
  import numpy
  import pytest
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  from ...testing import assert_arrays_equal, clear_and_catch_warnings
  from ..None import tractogram
  from ..tractogram import LazyDict, LazyTractogram, PerArrayDict, PerArraySequenceDict, Tractogram, TractogramItem, is_data_dict, is_lazy_dict
label_desc: Use image node_id 4 for calling a global function with example usage: setup_module() without return types