PySerial App runs in shell, by not py script

Question

I have a very simple python script that uses pySerial to send data over the serial port to my Arduino. When I execute this line-by-line in the python shell, it works just f

Answer 1

import serial
import time 

ser = serial.Serial('/dev/ttyACM1', 9600, timeout=1)
time.sleep(3)      # this will needed for initializing arduino
serial.write(b'1') # b is necessary for byte