docs: Error when importing packages from pydantic [docs] (#16564)
URL : https://python.langchain.com/docs/use_cases/extraction
Desc:
<b> While the following statement executes successfully, it throws an
error which is described below when we use the imported packages</b>
```py
from pydantic import BaseModel, Field, validator
```
Code:
```python
from langchain.output_parsers import PydanticOutputParser
from langchain.prompts import (
PromptTemplate,
)
from langchain_openai import OpenAI
from pydantic import BaseModel, Field, validator
# Define your desired data structure.
class Joke(BaseModel):
setup: str = Field(description="question to set up a joke")
punchline: str = Field(description="answer to resolve the joke")
# You can add custom validation logic easily with Pydantic.
@validator("setup")
def question_ends_with_question_mark(cls, field):
if field[-1] != "?":
raise ValueError("Badly formed question!")
return field
```
Error:
```md
PydanticUserError: The `field` and `config` parameters are not available
in Pydantic V2, please use the `info` parameter instead.
For further information visit
https://errors.pydantic.dev/2.5/u/validator-field-config-info
```
Solution:
Instead of doing:
```py
from pydantic import BaseModel, Field, validator
```
We should do:
```py
from langchain_core.pydantic_v1 import BaseModel, Field, validator
```
Thanks.
---------
Co-authored-by: Bagatur <baskaryan@gmail.com>
langchain
3c387bc1 - docs: Error when importing packages from pydantic [docs] (#16564)
