def test01():
    __cdbkernel__=create_scope()
    {m,n,p,q,r,s}::Indices(position=fixed);
    {m,n,p,q,r,s}::Integer(0..3);
    \Gamma{#}::GammaMatrix;
    \bar{#}::DiracBar;
    {\theta, \lambda, \psi, \chi}::Spinor;
    ex:=\bar{\theta} \Gamma_{m} \chi \bar{\psi} \Gamma^{m} \lambda;
    fierz(_, $\theta, \lambda, \psi, \chi$)
    tst:=-1/4 \bar{\theta} \Gamma_{m} \Gamma^{m} \lambda \bar{\psi}\chi - 1/4 \bar{\theta}\Gamma_{m}\Gamma^{n}\Gamma^{m} \lambda \bar{\psi}\Gamma_{n}\chi - 1/8 \bar{\theta}\Gamma_{m}\Gamma^{n p}\Gamma^{m}\lambda \bar{\psi}\Gamma_{p n}\chi - @(ex);
    assert(tst==0)
    print("Test 01 passed")
    
test01()