code: def test_ConstantDenseOutput():
      sol = ConstantDenseOutput(0, 1, np.array([1, 2]))
      assert_allclose(sol(1.5), [1, 2])
      assert_allclose(sol([1, 1.5, 2]), [[1, 1, 1], [2, 2, 2]])
  
      sol = ConstantDenseOutput(0, 1, np.array([]))
      assert_allclose(sol(1.5), np.empty(0))
      assert_allclose(sol([1, 1.5, 2]), np.empty((0, 3)))
  
imports: from itertools import product
  from numpy.testing import assert_, assert_allclose, assert_array_less, assert_equal, assert_no_warnings, suppress_warnings
  import pytest
  from pytest import raises
  import numpy
  from scipy.optimize._numdiff import group_columns
  from scipy.integrate import solve_ivp, RK23, RK45, DOP853, Radau, BDF, LSODA
  from scipy.integrate import OdeSolution
  from scipy.integrate._ivp.common import num_jac
  from scipy.integrate._ivp.base import ConstantDenseOutput
  from scipy.sparse import coo_matrix, csc_matrix
label_desc: Use image node_id 35 for calling a global function with example usage: test_ConstantDenseOutput() without return types