convert-ip4-to-6to4-address.py

#!/usr/bin/env python3
"""Convert ip address to  RFC3056 IPv6 6to4 address."""
import binascii
import ipaddress

ip4str = input("Enter IPv4 (e.g., 9.254.253.252):")
ip4 = ipaddress.IPv4Address(ip4str)
h = binascii.hexlify(ip4.packed).decode()
ip6 = ipaddress.IPv6Address("2002:" + h[:4] + ":" + h[4:] + "::")

print()
print("ip4 address:           ", ip4)
print("Integer (decimal):     ", int(ip4))
print("Integer (binary):      ", bin(int(ip4))[2:])
print("Ingeger (hexadecimal): ", h)
assert len(h) == 8
print("6to4 address:          ", ip6)
assert ip6.sixtofour == ip4