code: def teardown_module():
      global gtab_3s, signal_sph, msignal_sph, DWI, MDWI
      global bvecs, gtab, params_single, params_multi, MKgt_multi
      global bvals_3s, MDgt_multi, S0gt_multi, MKgt, MDgt
  
      gtab_3s, signal_sph, msignal_sph, DWI, MDWI = (
          None,
          None,
          None,
          None,
          None,
      )
      gtab, params_single, params_multi, MKgt_multi = (
          None,
          None,
          None,
          None,
      )
      bvals_3s, MDgt_multi, S0gt_multi, MKgt, MDgt = (
          None,
          None,
          None,
          None,
          None,
      )
      bvecs = None
  
file_path: dipy/dipy/reconst/tests/test_msdki.py
imports: import numpy
  import random
  from numpy.testing import assert_array_almost_equal, assert_raises, assert_almost_equal, assert_
  from dipy.sims.voxel import single_tensor, multi_tensor_dki
  from dipy.io.gradients import read_bvals_bvecs
  from dipy.core.gradients import gradient_table, unique_bvals_magnitude, round_bvals
  from dipy.data import get_fnames
  import dipy.reconst.msdki
  from dipy.reconst.msdki import msk_from_awf, awf_from_msk
label_desc: Use image node_id 2 for calling a global function with example usage: teardown_module() without return types