At first we create a php file and we name it: test.php.
$python = exec(`python hello.py`);
As we see, there is a variable called: $python. This variable keeps the output of hello.py file.
print "If you can read this inside a Web-Browser window, you can successfully run Python through XAMPP!'"
Now is time check if test.php is going to browse python's file message.
We save both files in a sub-directory of htdocs of xampp (let's call this sub-directory 'my_projects')
Now we type at url http://localhost/my_projects/hello.php.
We have to see in our browser the python's file message,as it looks below.