random int without random module

1def randint(a, b):
2    "Return random integer in range [a, b], including both end points."
3    return a + randbelow(b - a + 1)
4
5def randbelow(n):
6    "Return a random int in the range [0,n).  Raises ValueError if n<=0."
7    k = n.bit_length()
8    numbytes = (k + 7) // 8
9    while True:
10        r = int.from_bytes(random_bytes(numbytes), 'big')
11        r >>= numbytes * 8 - k
12        if r < n:
13            return r
14
15def random_bytes(n):
16    "Return n random bytes"
17    with open('/dev/urandom', 'rb') as file:
18        return file.read(n)
19        
20print(randint(1, 10000))