def _key2bin(s):
 kl = map((lambda x: ord(x)), s)
 kl = map((lambda x: (binary[(x / 16)] + binary[(x & 15)])), kl)
 return ''.join(kl)

def _key2bin ( s ) : kl = map ( ( lambda x : ord ( x ) ) , s ) kl = map ( ( lambda x : ( binary [ ( x / 16 ) ] + binary [ ( x & 15 ) ] ) ) , kl ) return '' . join ( kl )
convert a key into a string of binary digits .