def in6_getnsmac(a):
 a = struct.unpack('16B', a)[(-4):]
 mac = '33:33:'
 mac += ':'.join(map((lambda x: ('%.2x' % x)), a))
 return mac

def in6_getnsmac ( a ) : a = struct . unpack ( '16B' , a ) [ ( - 4 ) : ] mac = '33:33:' mac += ':' . join ( map ( ( lambda x : ( '%.2x' % x ) ) , a ) ) return mac
return the multicast mac address associated with provided ipv6 address .