PydanticImportError: BaseSettings has been moved

[laxa1986]

Hello dear all. In my project I use fastapi and dependency-injector
Today I upgradeded dedpendncy-injector 4.48.2 -> 4.48.3 after that I started to get an error in output (the app still works though)
OS: MacOS 15.6.1, Apple Silicon, tried on Python 3.13 and 3.14

Minimalistic app to reproduce the error:

from fastapi import FastAPI

if __name__ == '__main__':
    from dependency_injector import containers

Error itself:

Exception ignored in PyObject_HasAttr(); consider using PyObject_HasAttrWithError(), PyObject_GetOptionalAttr() or PyObject_GetAttr():
Traceback (most recent call last):
  File "/Users/alexc/agilecustoms/github/env-api/.venv/lib/python3.14/site-packages/pydantic/__init__.py", line 437, in __getattr__
    return _getattr_migration(attr_name)
  File "/Users/alexc/agilecustoms/github/env-api/.venv/lib/python3.14/site-packages/pydantic/_migration.py", line 304, in wrapper
    raise PydanticImportError(
pydantic.errors.PydanticImportError: `BaseSettings` has been moved to the `pydantic-settings` package. See https://docs.pydantic.dev/2.12/migration/#basesettings-has-moved-to-pydantic-settings for more details.

For further information visit https://errors.pydantic.dev/2.12/u/import-error

[ZipFile]

There were no changes regarding pydantic support in recent versions, so I guess the issue is that we assume that pydantic-settings is always installed, and fallback to importing settings from pydantic package. And from looks of it, seems like recent versions of pydantic become louder about deprecated imports. This should not be a problem that breaks your code, but I think we can rewrite code a bit to avoid triggering the warning.

[laxa1986]

yep, code is not breaking, just nasty error in logs
yes, I understand about assuming about pydantic-settings. Indeed my project has no pydantic-settings.
@ZipFile But one thing I wanted to highlight you: try this minimalistic app (4 lines) I wrote. It gives no warning with DI 4.48.2. And it starts to give this warning at 4.48.3

[ZipFile]

I've checked what's going on. Cython v3.2 improved error handling on imports. DI v4.48.3 was built with Cython v3.2, hence a proper warning is triggered now. But nevertheless, existing behavior would've triggered same error/warning in vanilla python. Fix is in abc79ef, but will be included in future releases, due to low severity.