How to replace a random zero with a 1?

Question

Python

import random
b = str(000000)
a = random.randint(1, 6)

What to do next, so that in "b" some zero has changed to the desired number?

Answer 1

import random
b=[]
for i in range(6):
    b.append('0')
a = random.randint(0, 5)
b[a] = '1'
c=''.join(b)
print(c)

Answer 2

from random import sample

b = '100000'
''.join(sample(b, k=len(b)))