code: def test_dense1():
      A = np.ones((6, 6))
      A[0, :3] = 0
      A[1, 3:] = 0
      A[3:, ::2] = -1
      A[3, :2] = 0
      A[4, 2:] = 0
      b = np.zeros(A.shape[0])
  
      A2 = A[[0, 1, 3, 4], :]
      b2 = np.zeros(4)
  
      A1, b1, status, message = _remove_redundancy(A, b)
      assert_allclose(A1, A2)
      assert_allclose(b1, b2)
      assert_equal(status, 0)
  
imports: from __future__ import division, print_function, absolute_import
  import numpy
  from numpy.testing import assert_, assert_allclose, assert_equal
  from .test_linprog import magic_square
  from scipy.optimize._remove_redundancy import _remove_redundancy
label_desc: Use image node_id 12 for calling a global function with example usage: test_dense1() without return types