python module_error ai_generated true

ImportError: cannot import name 'BaseModel' from 'pydantic'

ID: python/fastapi-import-error-pydantic

Also available as: JSON · Markdown · 中文
80%Fix Rate
85%Confidence
0Evidence
2024-11-18First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.x active — — —

Root Cause

Pydantic version is too old or not installed; BaseModel was introduced in v1.

generic

中文

Pydantic版本过旧或未安装；BaseModel从v1版本开始引入。

Workarounds

  1. 95% success Upgrade pydantic to a recent version. 
    pip install --upgrade pydantic
  2. 85% success If using pydantic v2, import from pydantic.v1. 
    from pydantic.v1 import BaseModel

Dead Ends

Common approaches that don't work:

  1. Installing an older version of pydantic that does not have BaseModel. 70% fail

    BaseModel is a core feature; older versions may not have it.

  2. Trying to import from pydantic.dataclasses instead. 60% fail

    That is a different feature; BaseModel is the standard way.