code: def test_spsolve_triangular(matrices):
      A_dense, A_sparse, b = matrices
      A_sparse = sparse.tril(A_sparse)
  
      x = splin.spsolve_triangular(A_sparse, b)
      assert_allclose(A_sparse @ x, b)
  
imports: import pytest
  import numpy
  import scipy.sparse
  import scipy.sparse.linalg
  from numpy.testing import assert_allclose
label_desc: Use image node_id 14 for calling a global function with example usage: test_spsolve_triangular(matrices) without return types