Secure panel meter Elite 440-446 Type-D3B using python. (#Modbus RTU)

Question

I want to know the starting address and number of registers/Count required. I am sharing screenshot below having little bit of my code and error it is generating. .

Some of the libraries I'm using in my code -

from pymodbus.client.sync import ModbusSerialClient as ModbusClient   
from pymodbus.exceptions import ModbusIOException   
from bitstring import BitArray.  

1. I want to know the output when I use the command print(AllReg) in the code given above.
2. I want to know the starting address and no. of registers/count so that I can vary starting address that is 0x64 and no. of register=0x70 in order to get correct output AllReg=client.read_holding_registers(0x64 , 0x70, unit=3)