all Python 3pdbfunction

pdb.pm()

post-mortem debugging

Post-mortem debugging of the last uncaught exception in an interactive session: python -i script.py, then pdb.pm().

Syntax

pdb.pm()

pm() reads sys.last_exc (sys.last_traceback before 3.12), and only the interactive interpreter sets them after an unhandled exception. A normal script has no such attributes and pm() fails with AttributeError; use post_mortem() inside except there. `python -m pdb script.py` enters post-mortem mode by itself.

Examples

import pdb
try:
    pdb.pm()
except AttributeError as e:
    print(type(e).__name__)  # → AttributeError — в скрипте нет sys.last_exc

See also

Common errors

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