import serial,sys
ser=serial.Serial('COM3',115200,xonxoff=1,timeout=2)
scr=""
try:
    while True:
        if ser.isOpen():
            chars=ser.read(2000)
            scr=scr+chars
            ser.write("\x1b[2J\x1b[0;0H")
            ser.flush()
            ser.write(scr)
finally:
    ser.close()