How to use the pywaves.crypto function in PyWaves

timestamp = int(time.time() * 1000)
            transfersData = b''
            for i in range(0, len(transfers)):
                transfersData += base58.b58decode(transfers[i]['recipient']) + struct.pack(">Q", transfers[i]['amount'])
            sData = b'\x0b' + \
                    b'\1' + \
                    base58.b58decode(self.publicKey) + \
                    b'\0' + \
                    struct.pack(">H", len(transfers)) + \
                    transfersData + \
                    struct.pack(">Q", timestamp) + \
                    struct.pack(">Q", txFee) + \
                    struct.pack(">H", len(attachment)) + \
                    crypto.str2bytes(attachment)

            signature = crypto.sign(self.privateKey, sData)

            data = json.dumps({
                "type": 11,
                "version": 1,
                "assetId": "",
                "senderPublicKey": self.publicKey,
                "fee": txFee,
                "timestamp": timestamp,
                "transfers": transfers,
                "attachment": base58.b58encode(crypto.str2bytes(attachment)),
                "signature": signature,
                "proofs": [
                    signature
                ]
            })

def getOrderHistory(self, assetPair, timestamp=0):
        if timestamp == 0:
            timestamp = int(time.time() * 1000)
        sData = base58.b58decode(self.publicKey) + \
                struct.pack(">Q", timestamp)
        signature = crypto.sign(self.privateKey, sData)
        data = {
            "Accept": "application/json",
            "Timestamp": str(timestamp),
            "Signature": signature
        }
        req = pywaves.wrapper('/matcher/orderbook/%s/%s/publicKey/%s' % ('WAVES' if assetPair.asset1.assetId=='' else assetPair.asset1.assetId, 'WAVES' if assetPair.asset2.assetId=='' else assetPair.asset2.assetId, self.publicKey), headers=data, host=pywaves.MATCHER)
        return req

def _generate(self, publicKey='', privateKey='', seed='', nonce=0):
        self.seed = seed
        self.nonce = nonce
        if not publicKey and not privateKey and not seed:
            wordCount = 2048
            words = []
            for i in range(5):
                r = crypto.bytes2str(os.urandom(4))
                x = (ord(r[3])) + (ord(r[2]) << 8) + (ord(r[1]) << 16) + (ord(r[0]) << 24)
                w1 = x % wordCount
                w2 = ((int(x / wordCount) >> 0) + w1) % wordCount
                w3 = ((int((int(x / wordCount) >> 0) / wordCount) >> 0) + w2) % wordCount
                words.append(wordList[w1])
                words.append(wordList[w2])
                words.append(wordList[w3])
            self.seed = ' '.join(words)
        if publicKey:
            pubKey = base58.b58decode(publicKey)
            privKey = ""
        else:
            seedHash = crypto.hashChain(struct.pack(">L", nonce) + crypto.str2bytes(self.seed))
            accountSeedHash = crypto.sha256(seedHash)
            if not privateKey:
                privKey = curve.generatePrivateKey(accountSeedHash)

timestamp = int(time.time() * 1000)

    sData = b'\4' + version + b'\4'

    if version == b'\2':
        sData += version

    sData += base58.b58decode(publicKey) + \
            (b'\1' + base58.b58decode(asset.assetId) if asset else b'\0') + \
            (b'\1' + base58.b58decode(feeAsset.assetId) if feeAsset else b'\0') + \
            struct.pack(">Q", timestamp) + \
            struct.pack(">Q", amount) + \
            struct.pack(">Q", txFee) + \
            base58.b58decode(recipient.address) + \
            struct.pack(">H", len(attachment)) + \
            pwcrypto.str2bytes(attachment)
    return sData