How can I detect if Python is running in Python Development Mode?

Question

To turn on Python Development Mode, you can use this flag:

python3 -X dev example.py

or use this environment variable:

PYTHONDEVMODE=1 python3 example.py

How can I write code within example.py to detect whether Python is running in Python Development Mode or not?

Does this answer your question? Check if my application runs in development/editable mode — Simon Hostettler
– Simon Hostettler, Commented Oct 23, 2020 at 14:01
if you use the environment var method you could check os.environ — rioV8
– rioV8, Commented Oct 23, 2020 at 14:09
@SimonHostettler No, that doesn't answer my question, as that question talks about editable mode, not Python Development Mode. — Flimm
– Flimm, Commented Oct 23, 2020 at 14:23
@rioV8 The variable __debug__ is True even when Python Development Mode is not on. I just tried it by running python3 and then running python3 -X dev — Flimm
– Flimm, Commented Oct 23, 2020 at 14:24

Syscall · Accepted Answer · 2022-01-16 14:20:57Z

3

sys.flags.dev_mode is True, when running as python -X dev app.py

Syscall

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answered Jan 16, 2022 at 13:34

Sameera K

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