Python Training Serail Recieve & CSV Saving

main.py

import datetime
import os
import serial
path = os.getcwd()
print(path)
print(type(path))
now = datetime.datetime.now()
filename =now.strftime('%Y%m%d_%H%M%S') + '.csv'
with open(filename, 'w',newline='')as f:
        writer = csv.writer(f)
        ser = serial.Serial("COM19", 115200)
        while True:
                val_arduino = ser.readline()
                txt = val_arduino.decode('utf8')
                str_arduino = txt.strip('\r\n')
                writer.writerow([str_arduino])
                print("str="+str_arduino)
                print(val_arduino)