[Python] The "context has already been set" error that occurs after importing a written Sanic...

Here, I must clarify that English is not my native language. If there are any grammar errors, please forgive me.

• python version: 3.10
• Sanic-Cors version: 2.2.0
• sanic version: 24.6.0
• OS: Win 11

I only extracted the simplest implementation, yet it still results in a Runtime Error, the following are detailed information.

I have tried to run api.py directly, and no errors occurred. When I was running main.py directly, an error occurred:

Main 2024-08-15 21:58:44 +0800 INFO: Sanic v24.6.0
Main 2024-08-15 21:58:44 +0800 INFO: Goin' Fast @ http://127.0.0.1:5050
Main 2024-08-15 21:58:44 +0800 INFO: app: ip
Main 2024-08-15 21:58:44 +0800 INFO: mode: production, single worker
Main 2024-08-15 21:58:44 +0800 INFO: server: sanic, HTTP/1.1
Main 2024-08-15 21:58:44 +0800 INFO: python: 3.12.4
Main 2024-08-15 21:58:44 +0800 INFO: platform: Windows-11-10.0.22631-SP0
Main 2024-08-15 21:58:44 +0800 INFO: packages: sanic-routing==23.12.0
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "xxx\Python\Python312\Lib\multiprocessing\spawn.py", line 122, in spawn_main
exitcode = _main(fd, parent_sentinel)
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "xxx\Python\Python312\Lib\multiprocessing\spawn.py", line 131, in _main
prepare(preparation_data)
File "xxx\Python\Python312\Lib\multiprocessing\spawn.py", line 246, in prepare
_fixup_main_from_path(data['init_main_from_path'])
File "xxx \Python\Python312\Lib\multiprocessing\spawn.py", line 297, in _fixup_main_from_path
main_content = runpy.run_path(main_path,
^^^^^^^^^^^^^^^^^^^^^^^^^
File "<frozen runpy>", line 286, in run_path
File "<frozen runpy>", line 98, in _run_module_code
File "<frozen runpy>", line 88, in _run_code
File "xxx\test\main.py", line 3, in <module>
api.start_server()
File "xxx\test\api.py", line 16, in start_server
app.run(host="127.0.0.1", port=5050)
File "xxx\Python\Python312\Lib\site-packages\sanic\mixins\startup.py", line 291, in run
serve(primary=self) # type: ignore
^^^^^^^^^^^^^^^^^^^
File "xxx\Python\Python312\Lib\site-packages\sanic\mixins\startup.py", line 1003, in serve
cls._set_startup_method()
File "xxx\Python\Python312\Lib\site-packages\sanic\mixins\startup.py", line 932, in _set_startup_method
set_start_method(method, force=cls.test_mode)
File "xxx\Python\Python312\Lib\multiprocessing\context.py", line 247, in set_start_method
raise RuntimeError('context has already been set')
RuntimeError: context has already been set


There is the first code file (api.py):

# api.py
from sanic import Sanic, json
from sanic_cors import CORS

app = Sanic("ip")
CORS(app)


@app.route("/get_proxy")
async def ip_api(request):
ip = "XXXXXX"
return json({"ip": ip})


def start_server():
app.run(host="127.0.0.1", port=5050)


if __name__ == '__main__':
start_server()


The second python file (main.py):

# main.py
import api

api.start_server()


I have guessed the Main Module Check ran for some reason, so I delete that code, but it didn't change anything.

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