code: def test_constant_cost_matrix():
      # Fixes #11602
      n = 8
      C = np.ones((n, n))
      row_ind, col_ind = linear_sum_assignment(C)
      assert_array_equal(row_ind, np.arange(n))
      assert_array_equal(col_ind, np.arange(n))
  
file_path: catboost/contrib/python/scipy/py3/scipy/optimize/tests/test_linear_assignment.py
imports: from numpy.testing import assert_array_equal
  from pytest import raises
  import pytest
  import numpy
  from scipy.optimize import linear_sum_assignment
  from scipy.sparse import random
  from scipy.sparse.sputils import matrix
  from scipy.sparse.csgraph import min_weight_full_bipartite_matching
  from scipy.sparse.csgraph.tests.test_matching import linear_sum_assignment_assertions, linear_sum_assignment_test_cases
label_desc: Use image node_id 2 for calling a global function with example usage: test_constant_cost_matrix() without return types