TypeError: cannot pickle '_io.TextIOWrapper' object

[fordguo]

my env:mac os ,python3.8.5,django 3.1
exception:
File "/Users/ford/workspace/products/ve/.venv/lib/python3.8/site-packages/django/core/management/base.py", line 371, in execute output = self.handle(*args, **options) File "/Users/ford/workspace/products/ve/.venv/lib/python3.8/site-packages/chroniker/management/commands/cron.py", line 342, in handle run_cron( File "/Users/ford/workspace/products/ve/.venv/lib/python3.8/site-packages/chroniker/management/commands/cron.py", line 214, in run_cron proc.start() File "/Users/ford/workspace/products/ve/.venv/lib/python3.8/site-packages/chroniker/utils.py", line 426, in start super(TimedProcess, self).start(*args, **kwargs) File "/usr/local/Cellar/[email protected]/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/multiprocessing/process.py", line 121, in start self._popen = self._Popen(self) File "/usr/local/Cellar/[email protected]/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/multiprocessing/context.py", line 224, in _Popen return _default_context.get_context().Process._Popen(process_obj) File "/usr/local/Cellar/[email protected]/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/multiprocessing/context.py", line 284, in _Popen return Popen(process_obj) File "/usr/local/Cellar/[email protected]/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/multiprocessing/popen_spawn_posix.py", line 32, in __init__ super().__init__(process_obj) File "/usr/local/Cellar/[email protected]/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/multiprocessing/popen_fork.py", line 19, in __init__ self._launch(process_obj) File "/usr/local/Cellar/[email protected]/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/multiprocessing/popen_spawn_posix.py", line 47, in _launch reduction.dump(process_obj, fp) File "/usr/local/Cellar/[email protected]/3.8.5/Frameworks/Python.framework/Versions/3.8/lib/python3.8/multiprocessing/reduction.py", line 60, in dump ForkingPickler(file, protocol).dump(obj) TypeError: cannot pickle '_io.TextIOWrapper' object

[cchurch]

According to https://docs.python.org/3.8/library/multiprocessing.html#contexts-and-start-methods:

Changed in version 3.8: On macOS, the spawn start method is now the default. The fork start method should be considered unsafe as it can lead to crashes of the subprocess.

To continue using the fork method anyways to avoid the error above, I added the following lines to myproject/__init__.py:

import multiprocessing
import sys

if sys.version_info[:2] == (3, 8) and sys.platform == 'darwin':
    multiprocessing.set_start_method('fork')