Graphic in python execution time

I want to graph the execution time of my algorithm in python, I've been trying with graph, but it doesn't work, any recommendation? this is my algorithm:

def countingSort(lista, maximo):
    maximo += 1
    conteo = [0] * maximo

    for n in lista:
      conteo[n] += 1

    aux = 0

    for j in range(maximo):
      for k in range(conteo[j]):
          lista[aux] = j
          aux += 1

    return lista


lista = [3, 7, 4, 1, 1, 1, 3, 1, 2, 7, 2,  4,  2,  6,  6,  5]
print("input: ",lista)


lista = countingSort(lista, max(lista))
print("output: ",lista)

input: [3, 7, 4, 1, 1, 1, 3, 1, 2, 7, 2, 4, 2, 6, 6, 5]
output: [1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 4, 5, 6, 6, 7, 7]