Incompatibility - psycopg2.errors not found in psycopg2cffi

[agger-magenta]

Documented in the session below.

Django's psycopg2 backend expect the errors member:

overnatningsafgift-init           |   File "/opt/pypy/lib/pypy3.10/site-packages/django/db/backends/postgresql/psycopg_any.py", line 77, in <module>
overnatningsafgift-init           |     from psycopg2 import errors, extensions, sql  # NOQA

This is how I reproduced:

>>> from psycopg2cffi import compat
... 
... compat.register()
... 
>>> import psycopg2
>>> from psycopg2 import errorcodes
>>> from psycopg2 import extensions
>>> from psycopg2 import sql
Traceback (most recent call last):
  File "<python-input-4>", line 1, in <module>
    from psycopg2 import sql
ImportError: cannot import name 'sql' from 'psycopg2cffi' (/home/agger/src/gronlandsprojekter/overnatningsafgift/venv/lib/python3.13/site-packages/psycopg2cffi/__init__.py)
>>> 
(venv) agger@thorfinn:~/src/gronlandsprojekter/overnatningsafgift$ pip install psycopg2-binary
Collecting psycopg2-binary
  Downloading psycopg2_binary-2.9.11-cp313-cp313-manylinux2014_x86_64.manylinux_2_17_x86_64.whl.metadata (4.9 kB)
Downloading psycopg2_binary-2.9.11-cp313-cp313-manylinux2014_x86_64.manylinux_2_17_x86_64.whl (4.2 MB)
   ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 4.2/4.2 MB 5.6 MB/s eta 0:00:00
Installing collected packages: psycopg2-binary
Successfully installed psycopg2-binary-2.9.11
(venv) agger@thorfinn:~/src/gronlandsprojekter/overnatningsafgift$ python
Python 3.13.5 (main, Jun 25 2025, 18:55:22) [GCC 14.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import psycopg2
>>> from psycopg2 import errors
>>> 

[agger-magenta]

I don't know if the problem simply boils down to this project not being in active development. But the errors member has been in psycopg2 since 2019 according to the release history: https://www.psycopg.org/docs/errors.html