def METHOD_NAME(nat_mean: Tensor, tril_nat_covar: Tensor) -> Tuple[Tensor, Tensor]:
    L = _triangular_inverse(tril_nat_covar, upper=False)
    mu = L @ (L.transpose(-1, -2) @ nat_mean.unsqueeze(-1))
    return mu.squeeze(-1), L
    # return nat_mean, L