Assumes that the decomposition is canonical.

def _kak_decomposition_to_operations(q0: ops.Qid,
                                     q1: ops.Qid,
                                     kak: linalg.KakDecomposition,
                                     allow_partial_czs: bool,
                                     atol: float = 1e-8
                                     ) -> List[ops.Operation]:
    """Assumes that the decomposition is canonical."""
    b0, b1 = kak.single_qubit_operations_before
    pre = [_do_single_on(b0, q0, atol=atol), _do_single_on(b1, q1, atol=atol)]
    a0, a1 = kak.single_qubit_operations_after
    post = [_do_single_on(a0, q0, atol=atol), _do_single_on(a1, q1, atol=atol)]

    return list(cast(Iterable[ops.Operation], ops.flatten_op_tree([
        pre,
        _non_local_part(q0,
                        q1,
                        kak.interaction_coefficients,
                        allow_partial_czs,
                        atol=atol),
        post,
    ])))