Start local PHP script w/ local Python script

The Python program I'm writing needs to start a local PHP script outside of Python's process. The program also needs to pass params to the PHP script. So far this seems to start the script:

os.syste开发者_运维技巧m( path_to_script_here param param )

However, I'm pretty certain that Python remains running until the PHP script is complete.

I've also looked at the various os.spawn methods and I'm not sure which would be appropriate for my case. Any ideas?

Thanks!

See: How to start a background process in Python?