shows a short recap of how to read different values by an env variables with Pydantic

pydantic_literal_recap.py

from typing import Union

from pydantic import BaseSettings, parse_obj_as
from typing_extensions import Literal


class LocalContext(BaseSettings):
    env: Literal["local"]  # 1
    mongo_url: str


class ProdContext(BaseSettings):
    env: Literal["prod"]  # 1
    mongo_url: str
    mongo_replicaset: str  # 2


Context = Union[LocalContext, ProdContext]  # 3

context = parse_obj_as(Context, {})  # 4