Lambda functions are not working

[actopozipc]

For some reason, the way the files get read in, lambda functions cant access variables in other scopes. Example to reproduce:

    a_values = []
    t_values = []
    für omega_m in [0.3,0.999,1.3]:
        liste(karte(lambda t_value: t_values.erweitere(karte(lambda a_value: np.real(t(a_value, t_value)), [omega_m])), np.arange(0,10,0.1)))

Throws an exception because a_values is not defined.