from dataclasses import dataclass


@dataclass
class Result[T, E]:
    value: T | None = None
    error: E | None = None

    @property
    def is_ok(self) -> bool:
        return self.error is None

    @property
    def is_err(self) -> bool:
        return self.error is not None

    @staticmethod
    def ok(value: T) -> "Result[T, E]":
        return Result(value=value)

    @staticmethod
    def err(error: E) -> "Result[T, E]":
        return Result(error=error)