Abjad errors

import abjad
import numpy as np

num = 4
den = 4

duration = abjad.Duration(num, den)
print("num: ", num, ", den: ", den, ", duration: ", duration)
nota = abjad.Note("c'", duration)
print(nota)


def durata(i):
    Numeratori      = [[4], [4, 3],     [4, 3],     [4, 3, 2],       [4, 3, 2],       [3, 2, 1],       [3, 2, 1],       [4, 3, 2],       [3, 2, 1],       [4, 3, 2],       [4, 3, 2],       [3, 2, 1],       [3, 2, 1],       [2, 1],     [2, 1],     [1]]
    ProbNumeratori  = [[1], [0.8, 0.2], [0.5, 0.5], [0.2, 0.5, 0.3], [0.2, 0.3, 0.5], [0.2, 0.5, 0.3], [0.2, 0.3, 0.5], [0.2, 0.5, 0.3], [0.2, 0.3, 0.5], [0.2, 0.5, 0.3], [0.2, 0.3, 0.5], [0.2, 0.5, 0.3], [0.2, 0.3, 0.5], [0.5, 0.5], [0.2, 0.8], [1]]

    Denominatori = [4, 4, 4, 4, 4, 4, 4, 8, 8, 16, 16, 16, 16, 16, 16, 16]

    num = np.random.choice(Numeratori[i], p=ProbNumeratori[i])
    den = Denominatori[i]
    print("num: ", num, "den: ", den)

    durataNota = abjad.Duration((num, den))
    print("duration: ", durataNota)

    return durataNota

for i in range(15):
    nota = abjad.Note("c", durata(i))
    print(nota)