Import Serial Port Error

[victorhe]

Hey, apologies for this very basic question. I am working in a clinical neuroscience lab and need help with Import Serial.
I have already installed pyserial in the Packages and I am currently using the USB TTL event marking module connected to BIOPAC.
I am trying to use this code:

import serial
ser = serial.Serial(0, 115200, timeout=1)
ser.write('01')
ser.write('00')
ser.close()

But I keep getting this error:

Traceback (most recent call last):
File "<string>", line 12, in <module>
File "C:\Users\FiercePC\Documents\Work\VR\Code.py", line 27, in <module>
ser = serial.Serial(0, 115200, timeout=1)
File "C:\Program Files\WorldViz\Vizard7\bin\lib\site-packages\pyserial-3.5-py3.8.egg\serial\serialwin32.py", line 33, in __init__
File "C:\Program Files\WorldViz\Vizard7\bin\lib\site-packages\pyserial-3.5-py3.8.egg\serial\serialutil.py", line 222, in __init__
File "C:\Program Files\WorldViz\Vizard7\bin\lib\site-packages\pyserial-3.5-py3.8.egg\serial\serialutil.py", line 268, in port
ValueError: "port" must be None or a string, not <class 'int'>

Can someone help? Thanks