def remove(self, elem):
        """Remove a requirement.

        :param elem: a string or :class:`Requirement` instance.
        """
        if isinstance(elem, text_type):
            for requirement in self:
                if requirement.package == elem:
                    return super(Requirements, self).remove(requirement)
        return super(Requirements, self).remove(elem)
def sls(n, d):
            gg = te.reduce_axis((0, lengths[n]))
            indices_idx = length_offsets[n] + gg
            data_idx = indices[indices_idx]
            data_val = data[data_idx, d]
            return te.sum(data_val, axis=gg)