How to get gdbm module?

Product Help
1

I’ve been using Conda for a few years as a convenient installation, mostly because I use Jupyter notebooks from time-to-time and it with all its dependencies installs with no problem.

At the moment, I’m working on a Python3 port of SpamBayes and am trying to fill in some missing modules. Gdbm is my current stumbling block:

% python
Python 3.9.13 (main, Aug 25 2022, 23:26:10)
[GCC 11.2.0] :: Anaconda, Inc. on linux
Type “help”, “copyright”, “credits” or “license” for more information.
>>> import dbm.gnu
Traceback (most recent call last):
File “”, line 1, in
File “/home/skip/miniconda3/envs/python39/lib/python3.9/dbm/gnu.py”, line 3, in
from _gdbm import *
ModuleNotFoundError: No module named ‘_gdbm’

I installed the conda gdbm package, but that just installed some shell level tools, not the desired dbm.gnu stuff. Python 3.10.4 seems to have it:

% /usr/bin/python3
Python 3.10.4 (main, Jun 29 2022, 12:14:53) [GCC 11.2.0] on linux
Type “help”, “copyright”, “credits” or “license” for more information.
>>> import dbm.gnu
>>> dir(dbm.gnu)
(‘builtins’, ‘cached’, ‘doc’, ‘file’, ‘loader’, ‘name’, ‘package’, ‘spec’, ‘error’, ‘open’, ‘open_flags’)

I see nothing in conda search output which would suggest gdbm is available. I can switch to 3.10 without much trouble, but why gdbm is nowhere to be found in Conda.

1 Like
2

dear skip.montanaro.

Thank you for your posting.

The cause of the error is unknown, but “_gdbm.cpython-39-x86_64-linux-gnu.so”, which should exist under “/lib/python3.9/lib-dynload/”, does not exist. .

If another version of the corresponding library exists, copying it to the above directory will solve the problem.

Reference URL: python - No module named '_gdbm' - Stack Overflow

We apologize for the inconvenience, but thank you in advance.

Regards, you.
ktsh.tanaka.2020

3

Thanks. My Ubuntu system is already on 3.10, so the 3.9 workaround you mentioned isn’t available. I guess it’s time to create a python310 Conda environment.

4

dear skip.montanaro.

thank you for your reply.
To run gdbm with python3.10, it will be “_gdbm.cpython-310-x86_64-linux-gnu.so”, so please do not make a mistake.

I wish you every success.
Best regards
Ktsh.tanaka.2020

5

Yup, symlink does the trick and leaves evidence that something out of the ordinary happened.

7

dear skip.montanaro.

thank you for your reply.
You don’t really need a symbolic link.
Copy “_gdbm.cpython-310-x86_64-linux-gnu.so” directly to “/home/“user”/anaconda3/envs/py310/lib-dynload”.

after that,

sudo chown “user” _gdbm.cpython-310-x86_64-linux-gnu.so

must be implemented. Otherwise Python installed in anaconda will print import error again.

Best regards
ktsh.tananka.2020

8

Sure, but a symlink doesn’t require a sudo/chown step, and as I indicated, the fact that it’s a symlink leaves a little morsel suggesting something out of the ordinary is going on.