def colocate(self, others, why):
        """
        Colocate this operator with another.
        """
        if isinstance(self, Marker):
            return
        colocate_tag = '__spl_' + why + '$' + str(self.index)
        self._colocate_tag(colocate_tag)
        for op in others:
            op._colocate_tag(colocate_tag)
Colocate this operator with another.