How do I fix "ModuleNotFoundError: No module named 'crypt'"?

For new hashing, use a dedicated library (`passlib`, `bcrypt`, `argon2-cffi`) or `hashlib.scrypt`. To verify existing crypt(3) hashes, use `passlib.hash` — it implements the sha512_crypt/sha256_crypt schemes crypt produced. There is no stdlib replacement by design; do not try to reintroduce crypt. Re-test on Python 3.13. Source: https://docs.python.org/3/whatsnew/3.13.html

Python 3.13

ModuleNotFoundError: No module named 'crypt'

Q: What does "ModuleNotFoundError: No module named 'crypt'" mean?

The crypt module was removed in Python 3.13 (PEP 594). crypt (Unix password hashing) was deprecated in 3.11 and removed in 3.13. Code that hashed or verified system-style passwords with crypt.crypt breaks on a python3.13 runtime.

ModuleNotFoundError: No module named 'crypt'

What it means

The crypt module was removed in Python 3.13 (PEP 594).

Why it happens

crypt (Unix password hashing) was deprecated in 3.11 and removed in 3.13. Code that hashed or verified system-style passwords with crypt.crypt breaks on a python3.13 runtime.

How to fix it

For new hashing, use a dedicated library (`passlib`, `bcrypt`, `argon2-cffi`) or `hashlib.scrypt`.
To verify existing crypt(3) hashes, use `passlib.hash` — it implements the sha512_crypt/sha256_crypt schemes crypt produced.
There is no stdlib replacement by design; do not try to reintroduce crypt.
Re-test on Python 3.13.

Related deadline: Lambda Python 3.11 EOL — 2027-07-31.

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Primary source: https://docs.python.org/3/whatsnew/3.13.html

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