Python CRC for cashcode driver (From JS to Python)

Question

I try to re-write CCNET driver for CashCode, from node to Python. But, i realy can`t run CRC generator.

You can find "working" code on Github repo

Here is the JS function:

function getCRC16(bufData) {
    var POLYNOMIAL = 0x08408;
    var sizeData = bufData.length;
    var CRC, i, j;
    CRC = 0;
    for (i = 0; i < sizeData; i++) {
        CRC ^= bufData[i];
        for (j = 0; j < 8; j++) {
            if (CRC & 0x0001) {
                CRC >>= 1;
                CRC ^= POLYNOMIAL;
            } else CRC >>= 1;
        }
    }

    var buf = new Buffer(2);
    buf.writeUInt16BE(CRC, 0);
    CRC = buf;

    return Array.prototype.reverse.call(CRC);
}

I try crcmod , BUT it`s not predefined function, and when i try set polynominal, get error

Here is my sometime working code:

@staticmethod
    def getCRC16(data):
        CRC = 0
        for i in range(0, len(data), 2):
            CRC ^= int(str(data[i:(i+2)]), 16)
            for j in range(8):
                if (CRC & 0x0001):
                    CRC >>= 1
                    CRC ^= 0x8408
                else:
                    CRC >>= 1
        CRC = format(CRC, '02x')
        return CRC[2:4] + CRC[0:2]

And i get

CRC ^= int(str(data[i:(i+2)]), 16)
ValueError: invalid literal for int() with base 16: '\x02\x03'

Help me with that function. (input binary/integers or HEX-strings)

UPD: : It works with bytearray.fromhex(data) . Thanks)

@staticmethod 
def getCRC16(data):
    data = bytearray.fromhex(data)
    CRC = 0
    for bit in data:
        CRC ^= bit
        for j in range(0, 8):
            if (CRC & 0x0001):
                CRC >>= 1
                CRC ^= 0x8408
            else:
                CRC >>= 1
    CRC = format(CRC, '02x')
    return CRC[2:4] + CRC[0:2]

Answer 1

Sinse Python 2.6: bytearray.fromhex(data).

E.G.

for byte in bytearray.fromhex(data):
CRC ^= byte
...