code: def test_orientation_from_to_string():
      with clear_and_catch_warnings():
          ras = np.array(((0, 1), (1, 1), (2, 1)))
          lps = np.array(((0, -1), (1, -1), (2, 1)))
          asl = np.array(((1, 1), (2, 1), (0, -1)))
          npt.assert_array_equal(orientation_from_string("ras"), ras)
          npt.assert_array_equal(orientation_from_string("lps"), lps)
          npt.assert_array_equal(orientation_from_string("asl"), asl)
          npt.assert_raises(ValueError, orientation_from_string, "aasl")
  
          assert orientation_to_string(ras) == "ras"
          assert orientation_to_string(lps) == "lps"
          assert orientation_to_string(asl) == "asl"
  
imports: import warnings
  import numpy
  import numpy.testing
  import pytest
  from dipy.data import get_fnames
  from dipy.core.gradients import b0_threshold_empty_gradient_message, b0_threshold_update_slicing_message, gradient_table, GradientTable, gradient_table_from_bvals_bvecs, gradient_table_from_qvals_bvecs, gradient_table_from_gradient_strength_bvecs, WATER_GYROMAGNETIC_RATIO, mask_non_weighted_bvals, orientation_to_string, reorient_bvecs, generate_bvecs, check_multi_b, round_bvals, get_bval_indices, unique_bvals_magnitude, unique_bvals_tolerance, unique_bvals, params_to_btens, btens_to_params, orientation_from_string, reorient_vectors
  from dipy.core.geometry import vec2vec_rotmat, vector_norm
  from dipy.io.gradients import read_bvals_bvecs
  from dipy.utils.deprecator import ExpiredDeprecationError
  from dipy.testing import clear_and_catch_warnings
  from dipy.testing.decorators import set_random_number_generator
label_desc: Use image node_id 24 for calling a global function with example usage: test_orientation_from_to_string() without return types