IPv6

From David's Wiki
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Local Addresses

See https://datatracker.ietf.org/doc/html/rfc4193#section-3

The summary is that your subnet is commonly a /64 where the first 8 bits are 0xFD, the next 40 bits are random, and the last 16 bits are a subnet ID of your choosing. The 40 random bits make collisions unlikely.

import random <br />

prefix = f"{0b11111101:02x}" # 0xfd
random_bits = f"{random.getrandbits(40):010x}" # 40 random bits
# subnet_id = f"{random.getrandbits(16):04x}" # 16 bits of your choice
subnet_id = "0000"
ip = prefix + random_bits + subnet_id
ip = ":".join((ip[4*x:4*x+4] for x in range(len(ip)//4)))
print(ip)