'Create SNAP packet'

def __init__(self, DAB=None, SAB=None, ACK=None, NAK=None, dataBytes=None):

    self.bytes = []
    self.encoded = False
    if ((DAB != None) and (SAB != None) and (ACK != None) and (NAK != None) and (dataBytes != None)):
        self.SYNC = SYNC_BYTE
        self.DAB = DAB
        self.SAB = SAB
        self.ACK = ACK
        self.NAK = NAK
        self.dataBytes = dataBytes
        self.decoded = True
    else:
        self.SYNC = None
        self.decoded = False
