Trigger SystemExit upon init in non-interactive editor

import pytest
from nbproject import header

# header() this should be ignored

with pytest.raises(SystemExit):
    header(
        parent=["z14KWQKD4bwE", "r4Dkcgt2HIfh"], pypackage="anndata"
    )  # header() triggers exit init

ℹ️ Initializing.