OverflowError: Python int too large to convert to C long

def floatToWords(self, value):
        s = struct.pack('f', value).encode('hex')
        word1 = int(s, 16)
        word2 = int(s[2:4], 16)
        return word1, word2

words = self.floatToWords(concentration)
modbus.write_input_register(self.modbusAddress['concentration'],   words[0])
modbus.write_input_register(self.modbusAddress['concentration']+1, words[1])