How to create Singleton with process control?

Question

Django

there is a long process that only superuser has access to.
is launched in another thread, similar to the article .
how to make a singleton with the ability to control employment, that is, when accessing it, either a process is started, or a message is returned that the process is already running?

Answer 1

Singleton has nothing to do with it.
You need inter-process communication facilities.
from multiprocessing import Lock

Answer 2

Create a file and check for its existence
Or write a label to the database