code: def test_kron(self):
      cases = []
  
      cases.append(array([[0]]))
      cases.append(array([[-1]]))
      cases.append(array([[4]]))
      cases.append(array([[10]]))
      cases.append(array([[0], [0]]))
      cases.append(array([[0, 0]]))
      cases.append(array([[1, 2], [3, 4]]))
      cases.append(array([[0, 2], [5, 0]]))
      cases.append(array([[0, 2, -6], [8, 0, 14]]))
      cases.append(array([[5, 4], [0, 0], [6, 0]]))
      cases.append(array([[5, 4, 4], [1, 0, 0], [6, 0, 8]]))
      cases.append(array([[0, 1, 0, 2, 0, 5, 8]]))
      cases.append(array([[0.5, 0.125, 0, 3.25], [0, 2.5, 0, 0]]))
  
      for a in cases:
          for b in cases:
              result = construct.kron(
                  csr_matrix(a), csr_matrix(b)
              ).todense()
              expected = np.kron(a, b)
              assert_array_equal(result, expected)
  
imports: from __future__ import division, print_function, absolute_import
  import numpy
  from numpy import array
  from numpy.testing import assert_equal, assert_, assert_array_equal, assert_array_almost_equal_nulp
  import pytest
  from pytest import raises
  from scipy._lib._testutils import check_free_memory
  from scipy.sparse import csr_matrix, coo_matrix, construct
  from scipy.sparse.construct import rand
  from scipy.sparse.sputils import matrix
label_desc: Use image node_id 13 for calling the TestConstructUtils obj's underlying member method code with example usage: obj.test_kron() without return types