"ServerSentEvent. Use 'data' for JSON-serialized payloads "
                "or 'raw_data' for pre-formatted strings."
            )
        return self


def format_sse_event(
    *,
    data_str: Annotated[
        str | None,
        Doc(
            """
            Pre-serialized data string to use as the `data:` field.
            """
        ),
    ] = None,

    ResponseValidationError,
    WebSocketRequestValidationError,
)
from fastapi.sse import (
    _PING_INTERVAL,
    KEEPALIVE_COMMENT,
    EventSourceResponse,
    ServerSentEvent,
    format_sse_event,
)
from fastapi.types import DecoratedCallable, IncEx
from fastapi.utils import (
    create_model_field,
    generate_unique_id,
    get_value_or_default,
    is_body_allowed_for_status_code,
)