def is_subset(self, values):
        """Checks whether this expression's contents, which must resolve to an
        array, are a subset of the given array or array expression's contents.

        The arrays are treated as sets, so duplicate values are ignored.

        Examples::

            import fiftyone as fo
            from fiftyone import ViewField as F

            dataset = fo.Dataset()
            dataset.add_samples(
                [
                    fo.Sample(
                        filepath="image1.jpg",
                        tags=["a", "b", "a", "b"],
                        other_tags=["a", "b", "c"],
                    )
                ]
            )

            print(dataset.values(F("tags").is_subset(F("other_tags"))))
            # [True]

        Args:
            values: an iterable of values or a :class:`ViewExpression` that
                resolves to an array

        Returns:
            a :class:`ViewExpression`
        """
        if isinstance(values, ViewExpression):
            other = values
        else:
            other = list(values)

        return ViewExpression({"$setIsSubset": [self, other]})
Checks whether this expression's contents, which must resolve to an
        array, are a subset of the given array or array expression's contents.

        The arrays are treated as sets, so duplicate values are ignored.

        Examples::

            import fiftyone as fo
            from fiftyone import ViewField as F

            dataset = fo.Dataset()
            dataset.add_samples(
                [
                    fo.Sample(
                        filepath="image1.jpg",
                        tags=["a", "b", "a", "b"],
                        other_tags=["a", "b", "c"],
                    )
                ]
            )

            print(dataset.values(F("tags").is_subset(F("other_tags"))))
            # [True]

        Args:
            values: an iterable of values or a :class:`ViewExpression` that
                resolves to an array

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