def serialize(self):
    r = b''
    r += self.prevout.serialize()
    r += ser_string(self.scriptSig)
    r += struct.pack('<I', self.nSequence)
    return r
def serialize(self):
    r = b
    r += self.prevout.serialize()
    r += ser_string(self.scriptSig)
    r += struct.pack('<I', self.nSequence)
    return r