def bswap(value):
 (hi, lo) = struct.unpack('>II', struct.pack('<Q', value))
 return ((hi << 32) | lo)

def bswap ( value ) : ( hi , lo ) = struct . unpack ( '>II' , struct . pack ( '<Q' , value ) ) return ( ( hi << 32 ) | lo )
a byte-swap instruction in python .