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The parallelization problem occurs when n_jobs is -1 and task is ts_forecasting.

The script to reproduce:

https://github.com/nccr-itmo/FEDOT/blob/ts-bug/cases/ts_exp.py

The error:

     File "D:\Projects\CompositeAutoML\fedot\core\optimisers\gp_comp\operators\evaluation.py", line 49, in __call__
        evaluated_population = self.evaluate_dispatch(reversed_population)
      File "D:\Projects\CompositeAutoML\fedot\core\optimisers\gp_comp\operators\evaluation.py", line 61, in evaluate_dispatch
        with closing(multiprocessing.Pool(n_jobs)) as pool:
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\context.py", line 119, in Pool
        return Pool(processes, initializer, initargs, maxtasksperchild,
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\pool.py", line 212, in __init__
        self._repopulate_pool()
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\pool.py", line 303, in _repopulate_pool
        return self._repopulate_pool_static(self._ctx, self.Process,
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\pool.py", line 326, in _repopulate_pool_static
        w.start()
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\process.py", line 121, in start
        self._popen = self._Popen(self)
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\context.py", line 326, in _Popen
        return Popen(process_obj)
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\popen_spawn_win32.py", line 45, in __init__
        prep_data = spawn.get_preparation_data(process_obj._name)
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\spawn.py", line 154, in get_preparation_data
        _check_not_importing_main()
      File "C:\Users\Nikolay\AppData\Local\Programs\Python\Python38\lib\multiprocessing\spawn.py", line 134, in _check_not_importing_main
        raise RuntimeError('''
    RuntimeError: 
    An attempt has been made to start a new process before the
    current process has finished its bootstrapping phase.

    This probably means that you are not using fork to start your
    child processes and you have forgotten to use the proper idiom
    in the main module:

        if __name__ == '__main__':
            freeze_support()
            ...

    The "freeze_support()" line can be omitted if the program
    is not going to be frozen to produce an executable.