how can i select parents using tournament selection

Question

I'm create this code but now I need select parents using the tournament selection and if I enter an odd number like 5 the program don't should give me 5 parents should give me 4 parents

this is what I have

please if any can help me

import random
import math
po =[]
num_rand_num = int(input(f"Digite cuantos numeros aleatorios quiere: "))
for _ in range (num_rand_num):
    rand_num = random.randint(0,30)
    po.append(rand_num)
    
print(po)

ap = []
for x in po:
    aptitud = x ** 3 * math.sin(x) + x + 2
    ap.append(aptitud)

print (f"La aptitud de los numeros es de:\n {ap} ")

Answer 1

import random
import math
po =[]
num_rand_num = int(input(f"Digite cuantos numeros aleatorios quiere: "))
for _ in range (num_rand_num - (num_rand_num % 2)):
    rand_num = random.randint(0,30)
    po.append(rand_num)
    
print(po)

ap = []
for x in po:
    aptitud = x ** 3 * math.sin(x) + x + 2
    ap.append(aptitud)

print (f"La aptitud de los numeros es de:\n {ap} ")