Philipp Sandhaus

Not compatible with Python 3.8

1

Using this with python 3.8 leads to the following error: ``` TRUE, pout = os.popen4('/bin/bash -c /usr/local/bin/BluetoothConnector') ``` `AttributeError:` module 'os' has no attribute 'popen4'`

## Summary - import construct's `this` helper - use variable-length buffer in `write_cmd` based on `data_length` ## Testing - `python -m py_compile protocol.py` - `pytest -q` ------ https://chatgpt.com/codex/tasks/task_e_68ad6a955ee48324ac8076bdc358e936