Reading from a serial port in Python

read_serial.py

import serial
from argparse import ArgumentParser

parser = ArgumentParser(description="UART reader for python enabled devices")

# positional arguments
parser.add_argument("device_location", help='device location through which serial data is communicated. Eg. dev/ttyACM0')
parser.add_argument("baud_rate", help='Baud rate in which serial data is communicated. Eg. 9600')
args = parser.parse_args()

# this port address is for the serial tx/rx pins on the GPIO header
SERIAL_PORT = args.device_location
# be sure to set this to the same rate used on the other device
SERIAL_RATE = args.baud_rate


def main():
    ser = serial.Serial(SERIAL_PORT, SERIAL_RATE)
    while True:
        # using ser.readline() assumes each line contains a single reading
        # sent using Serial.println() on the Arduino
        reading = ser.readline().decode('utf-8')
        # reading is a string...do whatever you want from here
        print(reading)


if __name__ == "__main__":
    main()