Hi there,

In an experiment, I need to work with another Python process (→ Python's multiprocessing module). The data exchange works via a pipe provided by the multiprocessing modul. This works in an oTree app.
However, I need to work with this connection across multiple apps. So, the idea is to store the connection object in a session field. 

But as soon as I try this, I get the exception:

Exception ignored in: <function _ConnectionBase.__del__ at 0x10aaca320>
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/multiprocessing/connection.py", line 137, in __del__
    self._close()
  File "/Library/Frameworks/Python.framework/Versions/3.10/lib/python3.10/multiprocessing/connection.py", line 366, in _close
    _close(self._handle)
OSError: [Errno 9] Bad file descriptor


Even though it is a very specific use case, maybe someone still has an idea what the problem could be.

Thanks a lot.