[Tkinter] how do I enter code into python

[matelot]

I am totally new to python. I have been asked to use python to solve another problem
I have gone through
https://python-forum.io/Thread-Basic-How...ython-code
without the answer.
From there I have deduced that I must build a file using something like wordpad, this I have done.
I now have a file called test.py containing.

## Rubik (Hello, World)    @ kas 2017

from tkinter import *
import serial, time
from serial import SerialException
import atexit
import subprocess

root =Tk()
root.title('Hello, World')
root.geometry('300x300+200+200')          

## window size + position

root.mainloop()

I have looked up tkinter and found it is a file that is included in the python download.
I am not sure about 'serial' is this within tkinter?
When I put c;users\bob\test.py (that is where the file is) into python all I get is
SyntaxError; unexpected character after line continuation character.
I assume I am doing something simple wrong but I have no idea what. Can you help?
thanks.