Add env_prefix to BaseSettings args

[Viicos]

Currently BaseSettings can take the following config values from its __init__ method:

pydantic-settings/pydantic_settings/main.py

Lines 47 to 54 in c05410f

	def __init__(
	__pydantic_self__,
	_env_file: DotenvType | None = env_file_sentinel,
	_env_file_encoding: str | None = None,
	_env_nested_delimiter: str | None = None,
	_secrets_dir: str | Path | None = None,
	**values: Any,
	) -> None:

Then these values are used if provided, else the ones from the SettingsConfigDict, e.g.:

pydantic-settings/pydantic_settings/main.py

Lines 109 to 114 in c05410f

	dotenv_settings = DotEnvSettingsSource(
	self.__class__,
	env_file=(_env_file if _env_file != env_file_sentinel else self.model_config.get('env_file')),
	env_file_encoding=(
	_env_file_encoding if _env_file_encoding is not None else self.model_config.get('env_file_encoding')
	),

Is there a reason why env_prefix isn't part of this scheme? If this is possible, I can make a PR implementing this.

[hramezani]

It's not only env_prefix. case_sensitive is not also included in __init__.

I think we can include both of them. PR welcome.

Please remember to update the docs and add proper tests

[Viicos]

Nice, will do