code: def test_immediate_updating(self):
      # check setting of immediate updating, with default workers
      bounds = [(0.0, 2.0), (0.0, 2.0)]
      solver = DifferentialEvolutionSolver(rosen, bounds)
      assert_(solver._updating == "immediate")
  
      # should raise a UserWarning because the updating='immediate'
      # is being overridden by the workers keyword
      with warns(UserWarning):
          with DifferentialEvolutionSolver(
              rosen, bounds, workers=2
          ) as solver:
              pass
      assert_(solver._updating == "deferred")
  
imports: import multiprocessing
  import platform
  from scipy.optimize._differentialevolution import DifferentialEvolutionSolver, _ConstraintWrapper
  from scipy.optimize import differential_evolution
  from scipy.optimize._constraints import Bounds, NonlinearConstraint, LinearConstraint
  from scipy.optimize import rosen
  from scipy.sparse import csr_matrix
  from scipy._lib._pep440 import Version
  import numpy
  from numpy.testing import assert_equal, assert_allclose, assert_almost_equal, assert_array_equal, assert_string_equal, assert_, suppress_warnings
  from pytest import raises, warns
  import pytest
label_desc: Use image node_id 37 for calling the TestDifferentialEvolutionSolver obj's underlying member method code with example usage: obj.test_immediate_updating() without return types