How to format IPv6 address in groups of 32 bits in Python

def format_ipv6addr_group2(addr):
    """
    Format IPv6 addresses in 4 \n-separated groups of 32 bits
    Returns a string
    """
    addr_s = str(addr.exploded)
    return f"{addr_s[:10]}\n{addr_s[10:20]}\n{addr_s[20:30]}\n{addr_s[30:40]}"

addr = ipaddress.IPv6Address("fd66:6cbb:8c10:1234:4567:89ab:cdef:0123")
print(format_ipv6addr_group2(addr))