Random password generator

import random
import string
all_letters = string.ascii_letters
all_numbers = string.digits
all_special = string.punctuation
all = all_letters+all_numbers+all_special

n = int(input("How many characters in your password?   "))

password = " "
for char in range(0,n):
    char = random.choice(all)
    password = password + char


print("your random password is :", password)