Construct a Filter that checks regex matches against ``pattern``.

        Parameters
        ----------
        pattern : str
            Regex pattern against which to compare values produced by ``self``.

        Returns
        -------
        matches : Filter
            Filter returning True for all sid/date pairs for which ``self``
            produces a string matched by ``pattern``.

        See Also
        --------
        :mod:`Python Regular Expressions <re>`

def matches(self, pattern):
        """
        Construct a Filter that checks regex matches against ``pattern``.

        Parameters
        ----------
        pattern : str
            Regex pattern against which to compare values produced by ``self``.

        Returns
        -------
        matches : Filter
            Filter returning True for all sid/date pairs for which ``self``
            produces a string matched by ``pattern``.

        See Also
        --------
        :mod:`Python Regular Expressions <re>`
        """
        return ArrayPredicate(
            term=self,
            op=LabelArray.matches,
            opargs=(pattern,),
        )