Displaying raspberry pi core temperature on a site

So I'm wondering, I found a script online that outputs the temperature of the raspberry pi every 2 seconds:

import os
import time

def measure_temp():
        temp = os.popen("vcgencmd measure_temp").readline()
        return (temp.replace("temp=",""))

while True:
        print(measure_temp())
        time.sleep(1)

I've also created a server and site using the standard apache method. In /var/www/html I have a file called 'phptest.php' that will makeup the site and I have a python file called 'monitor-temp.py' which contains the above code for outputting the temp.

My question is, how do I successfully add the python code to the php file and hence display the temperature on the site?

Can I literally just type out the python code into the php file using nano phptest.php? Or do I the php file to somehow access the python file.

I see a lot of guides saying to add this to the php file to execute the python code:

<?php
    $command = escapeshellcmd('/usr/custom/test.py');
    $output = shell_exec($command);
    echo $output;
?>

but that doesn't do anything for me. Thank you in advance!