FastAPI 0.98 breaks with pydantic 1.10.12

[desilinguist]

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Example Code

`conda create -n fastest python=3.11 fastapi=0.98.0`

Description

If I create a minimal virtual environment with fastapi=0.98.0 and python 3.11 using the conda command above, I cannot even import fastapi.

>>> import fastapi
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/nmadnani/anaconda/envs/pydantictest/lib/python3.11/site-packages/fastapi/__init__.py", line 7, in <module>
    from .applications import FastAPI as FastAPI
  File "/Users/nmadnani/anaconda/envs/pydantictest/lib/python3.11/site-packages/fastapi/applications.py", line 16, in <module>
    from fastapi import routing
  File "/Users/nmadnani/anaconda/envs/pydantictest/lib/python3.11/site-packages/fastapi/routing.py", line 24, in <module>
    from fastapi.dependencies.models import Dependant
  File "/Users/nmadnani/anaconda/envs/pydantictest/lib/python3.11/site-packages/fastapi/dependencies/models.py", line 3, in <module>
    from fastapi.security.base import SecurityBase
  File "/Users/nmadnani/anaconda/envs/pydantictest/lib/python3.11/site-packages/fastapi/security/__init__.py", line 1, in <module>
    from .api_key import APIKeyCookie as APIKeyCookie
  File "/Users/nmadnani/anaconda/envs/pydantictest/lib/python3.11/site-packages/fastapi/security/api_key.py", line 3, in <module>
    from fastapi.openapi.models import APIKey, APIKeyIn
  File "/Users/nmadnani/anaconda/envs/pydantictest/lib/python3.11/site-packages/fastapi/openapi/models.py", line 29, in <module>
    class Contact(BaseModel):
  File "pydantic/main.py", line 186, in pydantic.main.ModelMetaclass.__new__
TypeError: Argument 'bases' has incorrect type (expected list, got tuple)

However, if I downgrade to pydantic=1.10.11 from 1.10.12, then everything works.

Operating System

Linux, macOS

Operating System Details

macOS 13.5 onApple Silicon, macOS 13.4 on Intel

FastAPI Version

0.98.0

Python Version

3.11

Additional Context

No response

[desilinguist]

Actually, can confirm that fastapi 0.100.0 is also broken in the same way with pydantic 1.10.12 but works with pydantic 1.10.11.

[Kludex]

I can't reproduce it on 3.11.1 installing fastapi==0.98.0 and pydantic==1.10.12.

[desilinguist]

Thanks @Kludex! Looks like the issue was with the conda package for 1.10.12 (related to cython)

• I confirmed that the issue does not arise when using pip.
• conda-forge has yanked the 1.10.12 package so new deployments should now be okay.
• There's now a PR to fix the release: Fix 1.x release conda-forge/pydantic-feedstock#98