New GitHub issue #119592 from batterseapower:<br>

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<pre>
# Bug report

### Bug description:

```python
import time
from concurrent.futures import ProcessPoolExecutor

def fail():
 time.sleep(1)
    raise ValueError()

executor = ProcessPoolExecutor(max_workers=1, max_tasks_per_child=1)
try:
 print(executor.submit(fail).exception() is not None)
finally:
 executor.shutdown(wait=False)
```

If you run this, then the following is printed to the console:

```
Exception in thread Thread-1:
Traceback (most recent call last):
  File "python3.11/threading.py", line 1045, in _bootstrap_inner
    self.run()
  File "python3.11/concurrent/futures/process.py", line 364, in run
 executor._adjust_process_count()
  File "python3.11/concurrent/futures/process.py", line 759, in _adjust_process_count
    process_count = len(self._processes)
 ^^^^^^^^^^^^^^^^^^^^
TypeError: object of type 'NoneType' has no len()
```

If you change the code to using wait=True, or remove the max_tasks_per_child=1 option then the message is not printed.

Probably the fix is just to check if self.processes is None before accessing it at https://github.com/python/cpython/blob/main/Lib/concurrent/futures/process.py#L762

### CPython versions tested on:

3.11

### Operating systems tested on:

Linux
</pre>

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<a href="https://github.com/python/cpython/issues/119592">View on GitHub</a>
<p>Labels: type-bug</p>
<p>Assignee: </p>