The rem command is indeed for comments. It doesn’t inherently update anyone after running the script. Because by default the batch interpreter will print out each command before it’s processed, to avoid printing a command, prefix it with @, or, to apply that setting throughout the program, run @echo off. (It’s echo off to avoid printing further commands; the @ is to avoid printing that command prior to the echo setting taking effect.)
So, in your batch file, you might use this:
@echo off
REM To skip the following Python commands, put "REM" before them:
python foo.py