[BUG] Some tests fail

[yurivict]

runTest (pygmo.test.core_test_case) ... ERROR
runTest (pygmo._bfe_test.bfe_test_case) ... ok
runTest (pygmo._bfe_test.thread_bfe_test_case) ... ok
runTest (pygmo._bfe_test.member_bfe_test_case) ... ok
runTest (pygmo._bfe_test.mp_bfe_test_case) ... ok
runTest (pygmo._bfe_test.ipyparallel_bfe_test_case) ... ERROR
runTest (pygmo._bfe_test.default_bfe_test_case) ... ok
runTest (pygmo.test.archipelago_test_case) ... ERROR
runTest (pygmo._island_test.island_test_case) ... ok
runTest (pygmo._s_policy_test.s_policy_test_case) ... ok
runTest (pygmo._r_policy_test.r_policy_test_case) ... ok
runTest (pygmo._topology_test.topology_test_case) ... ok
runTest (pygmo.test.fair_replace_test_case) ... ok
runTest (pygmo.test.select_best_test_case) ... ok
runTest (pygmo.test.unconnected_test_case) ... ok
runTest (pygmo.test.ring_test_case) ... ok
runTest (pygmo.test.free_form_test_case) ... ok
runTest (pygmo.test.fully_connected_test_case) ... ok
runTest (pygmo.test.thread_island_test_case) ... ok
runTest (pygmo.test.thread_island_torture_test_case) ... ok
runTest (pygmo._problem_test.problem_test_case) ... ok
runTest (pygmo._algorithm_test.algorithm_test_case) ... /usr/local/lib/python3.9/site-packages/scipy/optimize/_minimize.py:569: RuntimeWarning: Method trust-exact cannot handle bounds.
  warn('Method %s cannot handle bounds.' % method,
/usr/local/lib/python3.9/site-packages/scipy/optimize/_minimize.py:569: RuntimeWarning: Method trust-krylov cannot handle bounds.
  warn('Method %s cannot handle bounds.' % method,
/usr/local/lib/python3.9/site-packages/scipy/optimize/_minimize.py:554: RuntimeWarning: Method L-BFGS-B does not use Hessian information (hess).
  warn('Method %s does not use Hessian information (hess).' % method,
/usr/local/lib/python3.9/site-packages/scipy/optimize/_trustregion_constr/projections.py:181: UserWarning: Singular Jacobian matrix. Using SVD decomposition to perform the factorizations.
  warn('Singular Jacobian matrix. Using SVD decomposition to ' +
/usr/local/lib/python3.9/site-packages/scipy/optimize/_hessian_update_strategy.py:182: UserWarning: delta_grad == 0.0. Check if the approximated function is linear. If the function is linear better results can be obtained by defining the Hessian as zero instead of using quasi-Newton approximations.
  warn('delta_grad == 0.0. Check if the approximated '
/usr/local/lib/python3.9/site-packages/pygmo/_py_algorithms.py:527: UserWarning: Problem Hock Schittkowski 71 has constraints and hessians, but trust-constr requires the callable to also accept lagrange multipliers. Thus, hessians of constraints are ignored.
  warnings.warn(
/usr/local/lib/python3.9/site-packages/scipy/optimize/_minimize.py:554: RuntimeWarning: Method SLSQP does not use Hessian information (hess).
  warn('Method %s does not use Hessian information (hess).' % method,
ok
runTest (pygmo._island_test.mp_island_test_case) ... ERROR
runTest (pygmo._island_test.ipyparallel_island_test_case) ... ERROR
runTest (pygmo.test.golomb_ruler_test_case) ... ok
runTest (pygmo.test.lennard_jones_test_case) ... ok
runTest (pygmo.test.de_test_case) ... ok
runTest (pygmo.test.nsga2_test_case) ... ok
runTest (pygmo.test.gaco_test_case) ... ok
runTest (pygmo.test.gwo_test_case) ... ok
runTest (pygmo.test.de1220_test_case) ... ok
runTest (pygmo.test.sea_test_case) ... ok
runTest (pygmo.test.pso_test_case) ... ok
runTest (pygmo.test.pso_gen_test_case) ... ok
runTest (pygmo.test.bee_colony_test_case) ... ok
runTest (pygmo.test.compass_search_test_case) ... ok
runTest (pygmo.test.sa_test_case) ... ok
runTest (pygmo.test.moead_test_case) ... ok
runTest (pygmo.test.moead_gen_test_case) ... ok
runTest (pygmo.test.sga_test_case) ... ok
runTest (pygmo.test.ihs_test_case) ... ok
runTest (pygmo.test.population_test_case) ... ok
runTest (pygmo.test.null_problem_test_case) ... ok
runTest (pygmo.test.hypervolume_test_case) ... ok
runTest (pygmo.test.mo_utils_test_case) ... ok
runTest (pygmo.test.con_utils_test_case) ... ok
runTest (pygmo.test.global_rng_test_case) ... ok
runTest (pygmo.test.estimate_sparsity_test_case) ... ok
runTest (pygmo.test.estimate_gradient_test_case) ... ok
runTest (pygmo.test.random_decision_vector_test_case) ... ok
runTest (pygmo.test.batch_random_decision_vector_test_case) ... ok
runTest (pygmo.test.cmaes_test_case) ... ok
runTest (pygmo.test.xnes_test_case) ... ok
runTest (pygmo.test.dtlz_test_case) ... ok
runTest (pygmo.test.cec2006_test_case) ... ok
runTest (pygmo.test.cec2009_test_case) ... ok
runTest (pygmo.test.cec2013_test_case) ... ok
runTest (pygmo.test.cec2014_test_case) ... ok
runTest (pygmo.test.luksan_vlcek1_test_case) ... ok
runTest (pygmo.test.minlp_rastrigin_test_case) ... ok
runTest (pygmo.test.rastrigin_test_case) ... ok
runTest (pygmo.test.translate_test_case) ... ok
runTest (pygmo.test.decompose_test_case) ... ok
runTest (pygmo.test.unconstrain_test_case) ... ok
runTest (pygmo.test.mbh_test_case) ... ok
runTest (pygmo.test.cstrs_self_adaptive_test_case) ... ok
runTest (pygmo.test.decorator_problem_test_case) ... ERROR
runTest (pygmo.test.constant_arguments_problem_test_case) ... ERROR
runTest (pygmo.test.wfg_test_case) ... ok
runTest (pygmo.test.nlopt_test_case) ... 
 objevals:        objval:      violated:    viol. norm:
         1         151341             18        1380.12 i
         6          11869             18        129.987 i
        11        3434.96             18        23.9871 i
        16        6.30533              2     0.00448389 i
        21        6.23246              0              0

Optimisation return status: NLOPT_XTOL_REACHED (value = 4, Optimization stopped because xtol_rel or xtol_abs was reached)

 objevals:        objval:      violated:    viol. norm:
         1         172656             18        819.045 i
         6        735.566             18        26.4699 i
        11        761.675             18        12.8251 i
        16        272.688             18         3.1034 i
        21        21.1561              4      0.0244414 i
        26        6.23246              0              0

Optimisation return status: NLOPT_XTOL_REACHED (value = 4, Optimization stopped because xtol_rel or xtol_abs was reached)
ok
runTest (pygmo.test.ipopt_test_case) ... 
******************************************************************************
This program contains Ipopt, a library for large-scale nonlinear optimization.
 Ipopt is released as open source code under the Eclipse Public License (EPL).
         For more information visit https://github.com/coin-or/Ipopt
******************************************************************************


 objevals:        objval:      violated:    viol. norm:
         1         149703             18        634.402 i
         6        106.993             18        6.09415 i
        11        6.23246              1    8.51876e-07 i

Optimisation return status: Solve_Succeeded (value = 0)

 objevals:        objval:      violated:    viol. norm:
         1         126514             18        490.192 i
         6        78988.6             18        73.6911 i
        11        1044.09              4      0.0109095 i
        16       0.903926              6      0.0168197 i
        21    6.21888e-13              0              0

Optimisation return status: Solve_Succeeded (value = 0)
ok

======================================================================
ERROR: runTest (pygmo.test.core_test_case)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/test.py", line 63, in runTest
    self.run_s11n_test()
  File "/usr/local/lib/python3.9/site-packages/pygmo/test.py", line 118, in run_s11n_test
    self.assertEqual(str(dill.loads(dill.dumps(isl))), str(isl))
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 263, in dumps
    dump(obj, file, protocol, byref, fmode, recurse, **kwds)#, strictio)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 235, in dump
    Pickler(file, protocol, **_kwds).dump(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 394, in dump
    StockPickler.dump(self, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 487, in dump
    self.save(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 578, in save
    rv = reduce(self.proto)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 263, in dumps
    dump(obj, file, protocol, byref, fmode, recurse, **kwds)#, strictio)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 235, in dump
    Pickler(file, protocol, **_kwds).dump(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 394, in dump
    StockPickler.dump(self, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 487, in dump
    self.save(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 603, in save
    self.save_reduce(obj=obj, *rv)
  File "/usr/local/lib/python3.9/pickle.py", line 687, in save_reduce
    save(cls)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1698, in save_type
    _save_with_postproc(pickler, (_create_type, (
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1070, in _save_with_postproc
    pickler.save_reduce(*reduction, obj=obj)
  File "/usr/local/lib/python3.9/pickle.py", line 692, in save_reduce
    save(args)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/pickle.py", line 901, in save_tuple
    save(element)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1186, in save_module_dict
    StockPickler.save_dict(pickler, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 971, in save_dict
    self._batch_setitems(obj.items())
  File "/usr/local/lib/python3.9/pickle.py", line 997, in _batch_setitems
    save(v)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 578, in save
    rv = reduce(self.proto)
  File "/usr/local/lib/python3.9/multiprocessing/pool.py", line 640, in __reduce__
    raise NotImplementedError(
NotImplementedError: pool objects cannot be passed between processes or pickled

======================================================================
ERROR: runTest (pygmo._bfe_test.ipyparallel_bfe_test_case)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/_bfe_test.py", line 521, in runTest
    ipyparallel_bfe.init_view(client_kwargs={'timeout': to})
  File "/usr/local/lib/python3.9/site-packages/pygmo/_py_bfes.py", line 391, in init_view
    ipyparallel_bfe._view = _make_ipyparallel_view(
  File "/usr/local/lib/python3.9/site-packages/pygmo/_ipyparallel_utils.py", line 12, in _make_ipyparallel_view
    from ipyparallel import Client
ImportError: cannot import name 'Client' from 'ipyparallel' (unknown location)

======================================================================
ERROR: runTest (pygmo.test.archipelago_test_case)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/test.py", line 871, in runTest
    self.run_pickle_tests()
  File "/usr/local/lib/python3.9/site-packages/pygmo/test.py", line 1303, in run_pickle_tests
    self.assertEqual(repr(a), repr(loads(dumps(a))))
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 263, in dumps
    dump(obj, file, protocol, byref, fmode, recurse, **kwds)#, strictio)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 235, in dump
    Pickler(file, protocol, **_kwds).dump(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 394, in dump
    StockPickler.dump(self, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 487, in dump
    self.save(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 578, in save
    rv = reduce(self.proto)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 263, in dumps
    dump(obj, file, protocol, byref, fmode, recurse, **kwds)#, strictio)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 235, in dump
    Pickler(file, protocol, **_kwds).dump(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 394, in dump
    StockPickler.dump(self, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 487, in dump
    self.save(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 603, in save
    self.save_reduce(obj=obj, *rv)
  File "/usr/local/lib/python3.9/pickle.py", line 687, in save_reduce
    save(cls)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1698, in save_type
    _save_with_postproc(pickler, (_create_type, (
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1070, in _save_with_postproc
    pickler.save_reduce(*reduction, obj=obj)
  File "/usr/local/lib/python3.9/pickle.py", line 692, in save_reduce
    save(args)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/pickle.py", line 901, in save_tuple
    save(element)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1186, in save_module_dict
    StockPickler.save_dict(pickler, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 971, in save_dict
    self._batch_setitems(obj.items())
  File "/usr/local/lib/python3.9/pickle.py", line 997, in _batch_setitems
    save(v)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 578, in save
    rv = reduce(self.proto)
  File "/usr/local/lib/python3.9/multiprocessing/pool.py", line 640, in __reduce__
    raise NotImplementedError(
NotImplementedError: pool objects cannot be passed between processes or pickled

======================================================================
ERROR: runTest (pygmo._island_test.mp_island_test_case)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/_island_test.py", line 435, in runTest
    self.run_basic_tests()
  File "/usr/local/lib/python3.9/site-packages/pygmo/_island_test.py", line 524, in run_basic_tests
    self.assertEqual(str(loads(dumps(isl))), str(isl))
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 263, in dumps
    dump(obj, file, protocol, byref, fmode, recurse, **kwds)#, strictio)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 235, in dump
    Pickler(file, protocol, **_kwds).dump(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 394, in dump
    StockPickler.dump(self, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 487, in dump
    self.save(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 578, in save
    rv = reduce(self.proto)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 263, in dumps
    dump(obj, file, protocol, byref, fmode, recurse, **kwds)#, strictio)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 235, in dump
    Pickler(file, protocol, **_kwds).dump(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 394, in dump
    StockPickler.dump(self, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 487, in dump
    self.save(obj)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 603, in save
    self.save_reduce(obj=obj, *rv)
  File "/usr/local/lib/python3.9/pickle.py", line 687, in save_reduce
    save(cls)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1698, in save_type
    _save_with_postproc(pickler, (_create_type, (
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1070, in _save_with_postproc
    pickler.save_reduce(*reduction, obj=obj)
  File "/usr/local/lib/python3.9/pickle.py", line 692, in save_reduce
    save(args)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/pickle.py", line 901, in save_tuple
    save(element)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 560, in save
    f(self, obj)  # Call unbound method with explicit self
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 1186, in save_module_dict
    StockPickler.save_dict(pickler, obj)
  File "/usr/local/lib/python3.9/pickle.py", line 971, in save_dict
    self._batch_setitems(obj.items())
  File "/usr/local/lib/python3.9/pickle.py", line 997, in _batch_setitems
    save(v)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 388, in save
    StockPickler.save(self, obj, save_persistent_id)
  File "/usr/local/lib/python3.9/pickle.py", line 578, in save
    rv = reduce(self.proto)
  File "/usr/local/lib/python3.9/multiprocessing/pool.py", line 640, in __reduce__
    raise NotImplementedError(
NotImplementedError: pool objects cannot be passed between processes or pickled

======================================================================
ERROR: runTest (pygmo._island_test.ipyparallel_island_test_case)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/_island_test.py", line 614, in runTest
    self.run_basic_tests()
  File "/usr/local/lib/python3.9/site-packages/pygmo/_island_test.py", line 633, in run_basic_tests
    ipyparallel_island.init_view(client_kwargs={'timeout': to})
  File "/usr/local/lib/python3.9/site-packages/pygmo/_py_islands.py", line 543, in init_view
    ipyparallel_island._view = _make_ipyparallel_view(
  File "/usr/local/lib/python3.9/site-packages/pygmo/_ipyparallel_utils.py", line 12, in _make_ipyparallel_view
    from ipyparallel import Client
ImportError: cannot import name 'Client' from 'ipyparallel' (unknown location)

======================================================================
ERROR: runTest (pygmo.test.decorator_problem_test_case)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/test.py", line 2569, in runTest
    a.wait_check()
RuntimeError: The asynchronous evolution of a pythonic island of type 'Multiprocessing island' raised an error:
multiprocessing.pool.RemoteTraceback: 
"""
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/multiprocessing/pool.py", line 125, in worker
    result = (True, func(*args, **kwds))
  File "/usr/local/lib/python3.9/site-packages/pygmo/_py_islands.py", line 25, in _evolve_func_mp_pool
    algo, pop = loads(ser_algo_pop)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 286, in loads
    return load(file, ignore, **kwds)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 272, in load
    return Unpickler(file, ignore=ignore, **kwds).load()
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 419, in load
    obj = StockUnpickler.load(self)
ModuleNotFoundError: No module named '__builtin__'
"""

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/_py_islands.py", line 246, in run_evolve
    return loads(res.get())
  File "/usr/local/lib/python3.9/multiprocessing/pool.py", line 771, in get
    raise self._value
ModuleNotFoundError: No module named '__builtin__'


======================================================================
ERROR: runTest (pygmo.test.constant_arguments_problem_test_case)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/test.py", line 2691, in runTest
    a.wait_check()
RuntimeError: The asynchronous evolution of a pythonic island of type 'Multiprocessing island' raised an error:
multiprocessing.pool.RemoteTraceback: 
"""
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/multiprocessing/pool.py", line 125, in worker
    result = (True, func(*args, **kwds))
  File "/usr/local/lib/python3.9/site-packages/pygmo/_py_islands.py", line 25, in _evolve_func_mp_pool
    algo, pop = loads(ser_algo_pop)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 286, in loads
    return load(file, ignore, **kwds)
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 272, in load
    return Unpickler(file, ignore=ignore, **kwds).load()
  File "/usr/local/lib/python3.9/site-packages/dill/_dill.py", line 419, in load
    obj = StockUnpickler.load(self)
ModuleNotFoundError: No module named '__builtin__'
"""

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/pygmo/_py_islands.py", line 246, in run_evolve
    return loads(res.get())
  File "/usr/local/lib/python3.9/multiprocessing/pool.py", line 771, in get
    raise self._value
ModuleNotFoundError: No module named '__builtin__'


----------------------------------------------------------------------
Ran 71 tests in 18.500s

FAILED (errors=7)
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/local/lib/python3.9/site-packages/pygmo/test.py", line 3076, in run_test_suite
    raise RuntimeError('One or more tests failed.')
RuntimeError: One or more tests failed.
*** Error code 1

Tests are run with the command:

python -c "import pygmo; pygmo.test.run_test_suite(1); pygmo.mp_island.shutdown_pool(); pygmo.mp_bfe.shutdown_pool()"

Version: 2.19.3
Python-3.9
FreeBSD 13.1

[bluescarni]

@yurivict I think this is the dill issue that has been already reported elsewhere.

Can you try to see if using dill==0.3.5.1 (or presumably even an older version) fixes the issue?

[gresavage]

@bluescarni I had the same issue and rolling back to dill==0.3.5.1 indeed fixed the issue