Label

class Label(StaticCollection):
    """
    An object for labeling datasets, models, and annotations.

    Attributes
    ----------
    key : String
        The class label key.
    value : String
        The class label value.
    score : Score
        The label score.

    Examples
    --------
    >>> Label(key="k1", value="v1")
    >>> Label(key="k1", value="v1", score=None)
    >>> Label(key="k1", value="v1", score=0.9)
    """

    key: String = String.symbolic(owner="label", name="key")
    value: String = String.symbolic(owner="label", name="value")
    score: Float = Float.symbolic(owner="label", name="score")

    def __init__(
        self,
        *,
        key: str,
        value: str,
        score: Union[float, np.floating, None] = None,
    ):
        """
        Initializes an instance of a label.

        Attributes
        ----------
        key : str
            The class label key.
        value : str
            The class label value.
        score : float, optional
            The label score.
        """
        super().__init__(key=key, value=value, score=score)

    @staticmethod
    def formatting() -> Dict[str, Any]:
        """Attribute format mapping."""
        return {
            "score": Float.nullable,
        }

    def tuple(self):
        """
        Defines how the `Label` is turned into a tuple.

        Returns
        ----------
        tuple
            A tuple of the `Label's` arguments.
        """
        return (self.key, self.value, self.score)