[Python] Python3 dictionary being modified at another trhead does not show changes after those...

Python version: (3.9, but the same result with python 3.12)

The goal was that another thread modified a dictionary and those modifications to be available at the original thread.

import multiprocessing as mp
import sys

def my_func(result: dict):
print(f'variable address at worker: {hex(id(result))}', file=sys.stderr)
result["test"] = "test"
print(f'{result}', file=sys.stderr)

result = {}
print(f'variable address at main thread: {hex(id(result))}', file=sys.stderr)
my_worker = lambda : my_func(result)

# execution at another Thread
p = mp.Process(target=my_worker)
p.start()
p.join()

print(f'result at main thread after execution: {result}', file=sys.stderr)

# manual execution
my_worker()
print(f'result at main thread after manual execution: {result}', file=sys.stderr)

print(sys.version)


and the output is:

variable address at main thread: 0x6ffffff39580
variable address at worker: 0x6ffffff39580
{'test': 'test'}
result at main thread after execution: {}
result at main thread after manual execution: {'test': 'test'}
3.9.16 (main, Mar 8 2023, 22:47:22)
[GCC 11.3.0]


My expectations were that result dictionary would show the changes done at the worker but it does not.

What am I doing wrong?

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