Jupyter Notebook导入chromadb时遇PydanticImportError求助

问题分析 #

你遇到的核心问题是：当前安装的Chromadb版本依赖Pydantic v1的BaseSettings类，但你的Python环境里装的是Pydantic v2——v2做了破坏性变更，把BaseSettings迁移到了独立的pydantic-settings包中。你自己导入pydantic-settings的操作无法解决问题，因为Chromadb自身的源码（比如chromadb/config.py）仍然直接从pydantic导入BaseSettings，这个路径在v2里已经不存在了。

可行解决方案 #

方案1：降级Pydantic到v1版本

直接将Pydantic降级到Chromadb兼容的v1稳定版本，这是最直接的解决办法：

pip install pydantic==1.10.12

执行完后重启Jupyter内核，再尝试导入chromadb即可。

方案2：启用Pydantic v1兼容模式

如果你不想降级Pydantic，可以通过设置环境变量让Pydantic模拟v1的导入逻辑，从而适配Chromadb的代码：

import os
os.environ["PYDANTIC_V1"] = "1"
import chromadb

这段代码需要放在导入chromadb之前执行。

方案3：升级Chromadb到兼容Pydantic v2的版本

检查Chromadb是否已经发布了支持Pydantic v2的版本，如果有，直接升级：

pip install --upgrade chromadb

升级后再尝试导入即可。

附错误日志参考 #

PydanticImportError                       Traceback (most recent call last)
Cell In[9], line 2
      1 from pydantic.v1 import BaseSettings
----> 2 import chromadb

File ~/.local/lib/python3.8/site-packages/chromadb/__init__.py:1
----> 1 import chromadb.config
      2 import logging
      3 from chromadb.telemetry.events import ClientStartEvent

File ~/.local/lib/python3.8/site-packages/chromadb/config.py:1
----> 1 from pydantic import BaseSettings
      2 from typing import List
      4 TELEMETRY_WHITELISTED_SETTINGS = ["chroma_db_impl", "chroma_api_impl", "chroma_server_ssl_enabled"]

File ~/.local/lib/python3.8/site-packages/pydantic/__init__.py:374, in __getattr__(attr_name)
    372 dynamic_attr = _dynamic_imports.get(attr_name)
    373 if dynamic_attr is None:
---> 374     return _getattr_migration(attr_name)
    376 package, module_name = dynamic_attr
    378 from importlib import import_module

File ~/.local/lib/python3.8/site-packages/pydantic/_migration.py:296, in getattr_migration.<locals>.wrapper(name)
    294     return import_string(REDIRECT_TO_V1[import_path])
    295 if import_path == 'pydantic:BaseSettings':
---> 296     raise PydanticImportError(
    297         '`BaseSettings` has been moved to the `pydantic-settings` package. '
    298         f'See https://docs.pydantic.dev/{version_short()}/migration/#basesettings-has-moved-to-pydantic-settings '
    299         'for more details.'
    300     )
    301 if import_path in REMOVED_IN_V2:
    302     raise PydanticImportError(f'`{import_path}` has been removed in V2.')

PydanticImportError: `BaseSettings` has been moved to the `pydantic-settings` package. See https://docs.pydantic.dev/2.6/migration/#basesettings-has-moved-to-pydantic-settings for more details.

For further information visit https://errors.pydantic.dev/2.6/u/import-error

内容的提问来源于stack exchange，提问作者MaveNeo