def decrypt(self, key, dev_addr):
sequence_counter = int(self.FCntUp)<EOL>return loramac_decrypt(self.payload_hex, sequence_counter, key, dev_addr)<EOL>
Decrypt the actual payload in this LoraPayload.

key: 16-byte hex-encoded AES key. (i.e. AABBCCDDEEFFAABBCCDDEEFFAABBCCDD)
dev_addr: 4-byte hex-encoded DevAddr (i.e. AABBCCDD)