code: def test_make_edge_pointers(a, expected):
      a = csr_matrix(a, dtype=np.int32)
      rev_edge_ptr = _make_edge_pointers(a)
      assert_array_equal(rev_edge_ptr, expected)
  
imports: import numpy
  from numpy.testing import assert_array_equal
  import pytest
  from scipy.sparse import csr_matrix, csc_matrix
  from scipy.sparse.csgraph import maximum_flow
  from scipy.sparse.csgraph._flow import _add_reverse_edges, _make_edge_pointers, _make_tails
label_desc: Use image node_id 15 for calling a global function with example usage: test_make_edge_pointers(a, expected) without return types