Tricky problem in the tutorial

[cheese-leopard]

Hi, I just started learning Lava a a few days ago and encountered a tricky problem during the tutorial. Using vscode and conda, I copied all the code in tutorial02_processes.ipynb. But at runtime, I found an error in the lif. run() method. After analyzing the error content, I found that the problem lies in spec.loader.exec_module(module) which belongs to line 850 of the compiler_graphs.py file. This method creates a Child process, but as far as I know, tutorial02 only needs one LIF process. May I ask what is the purpose of the .loader.exec_module() method? Thank you for your reply.

Specific error message as follows:

PS D:\ML> & D:/Anaconda3/envs/lava/python.exe d:/ML/test1.py
Traceback (most recent call last):
File "", line 1, in
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 116, in spawn_main
exitcode = _main(fd, parent_sentinel)
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 125, in _main
prepare(preparation_data)
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 236, in prepare
_fixup_main_from_path(data['init_main_from_path'])
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 287, in _fixup_main_from_path
main_content = runpy.run_path(main_path,
File "D:\Anaconda3\envs\lava\lib\runpy.py", line 288, in run_path
return _run_module_code(code, init_globals, run_name,
File "D:\Anaconda3\envs\lava\lib\runpy.py", line 97, in _run_module_code
_run_code(code, mod_globals, init_globals,
File "D:\Anaconda3\envs\lava\lib\runpy.py", line 87, in _run_code
exec(code, run_globals)
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.

[cheese-leopard]

When I run the code again, error message becomes different as follows:

UserWarning: Cannot import module '<module 'test' from 'd:\ML\test.py'>' when searching ProcessModels for Process 'LIF'.
warnings.warn(
Traceback (most recent call last):
File "", line 1, in
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 116, in spawn_main
exitcode = _main(fd, parent_sentinel)
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 125, in _main
prepare(preparation_data)
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 236, in prepare
_fixup_main_from_path(data['init_main_from_path'])
File "D:\Anaconda3\envs\lava\lib\multiprocessing\spawn.py", line 287, in _fixup_main_from_path
main_content = runpy.run_path(main_path,
File "D:\Anaconda3\envs\lava\lib\runpy.py", line 288, in run_path
return _run_module_code(code, init_globals, run_name,
File "D:\Anaconda3\envs\lava\lib\runpy.py", line 97, in _run_module_code
_run_code(code, mod_globals, init_globals,
File "D:\Anaconda3\envs\lava\lib\runpy.py", line 87, in _run_code
exec(code, run_globals)
File "d:\ML\test.py", line 88, in
lif.run(condition=RunSteps(num_steps=10), run_cfg=run_cfg)
File "D:\Anaconda3\envs\lava\lib\site-packages\lava\magma\core\process\process.py", line 350, in run
executable = self.compile(run_cfg, compile_config)
File "D:\Anaconda3\envs\lava\lib\site-packages\lava\magma\core\process\process.py", line 376, in compile
return compiler.compile(self, run_cfg)
File "D:\Anaconda3\envs\lava\lib\site-packages\lava\magma\compiler\compiler.py", line 129, in compile
proc_group_digraph = ProcGroupDiGraphs(process, run_cfg)
File "D:\Anaconda3\envs\lava\lib\site-packages\lava\magma\compiler\compiler_graphs.py", line 622, in init
proc_procmodel_map = ProcGroupDiGraphs._map_proc_to_model(proc_list,
File "D:\Anaconda3\envs\lava\lib\site-packages\lava\magma\compiler\compiler_graphs.py", line 1004, in _map_proc_to_model
models_cls = ProcGroupDiGraphs._find_proc_models(proc=proc)
File "D:\Anaconda3\envs\lava\lib\site-packages\lava\magma\compiler\compiler_graphs.py", line 822, in _find_proc_models
module_spec = importlib.util.find_spec(proc_module.name)
File "D:\Anaconda3\envs\lava\lib\importlib\util.py", line 114, in find_spec
raise ValueError('{}.spec is None'.format(name))
ValueError: mp_main.spec is None