Data validation and settings management using Python type hints.

Fast and extensible, pydantic plays nicely with your linters/IDE/brain. Define how data should be in pure, canonical Python 3.7+; validate it with pydantic.

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Install using pip install -U pydantic or conda install pydantic -c conda-forge. For more installation options to make pydantic even faster, see the Install section in the documentation.

from datetime import datetime
from typing import List, Optional
from pydantic import BaseModel
class User(BaseModel):
    id: int
    name = 'John Doe'
    signup_ts: Optional[datetime] = None
    friends: List[int] = []
external_data = {'id': '123', 'signup_ts': '2017-06-01 12:22', 'friends': [1, '2', b'3']}
user = User(**external_data)
print(user)
#> User id=123 name='John Doe' signup_ts=datetime.datetime(2017, 6, 1, 12, 22) friends=[1, 2, 3]
print(user.id)
#> 123

For guidance on setting up a development environment and how to make a contribution to pydantic, see Contributing to Pydantic.

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