def is_in(self, values):
        """Creates an expression that returns a boolean indicating whether
        ``self in values``.

        Examples::

            import fiftyone as fo
            import fiftyone.zoo as foz
            from fiftyone import ViewField as F

            ANIMALS = [
                "bear", "bird", "cat", "cow", "dog", "elephant", "giraffe",
                "horse", "sheep", "zebra"
            ]

            dataset = foz.load_zoo_dataset("quickstart")

            # Create a view that only contains animal predictions
            view = dataset.filter_labels(
                "predictions", F("label").is_in(ANIMALS)
            )

            print(view.count_values("predictions.detections.label"))

        Args:
            values: a value or iterable of values

        Returns:
            a :class:`ViewExpression`
        """
        if etau.is_str(values):
            values = [values]

        return ViewExpression({"$in": [self, list(values)]})
Creates an expression that returns a boolean indicating whether
        ``self in values``.

        Examples::

            import fiftyone as fo
            import fiftyone.zoo as foz
            from fiftyone import ViewField as F

            ANIMALS = [
                "bear", "bird", "cat", "cow", "dog", "elephant", "giraffe",
                "horse", "sheep", "zebra"
            ]

            dataset = foz.load_zoo_dataset("quickstart")

            # Create a view that only contains animal predictions
            view = dataset.filter_labels(
                "predictions", F("label").is_in(ANIMALS)
            )

            print(view.count_values("predictions.detections.label"))

        Args:
            values: a value or iterable of values

        Returns:
            a :class:`ViewExpression`
        
fiftyone/core/expressions.py