[Python] A solution to multiprocessing in Python without the if __name__ == '__main__' guard...

TLDR

Normally, any Python module that internally uses multiprocessing causes all scripts that import it to have to include the "guard" clause.

With the trick described, this guard is no longer necessary. People importing such a module in their scripts can write short and simple code - as if there was no multiprocessing involved.

Summarizing the problem

There are literally dozens of questions here on StackOverflow about spawning a process in Python using the multiprocessing module without using the

if __name__ == '__main__'
...


"guard" clause in the main Python 3 script.

Without this clause, multiprocessing will report a RuntimeError. (Otherwise, the main script running in the spawned process would create an infinite chain of its copies; this would quickly cause the program to eat up all RAM and freeze.) Thus it is usually recommended to accept the guard clause as a necessity for platform-independent multiprocessing in Python.

However, there are use cases where this "guard" is unacceptable. For example, I am developing a module which facilitates hardware control from Python using a Raspberry Pi pico device. On startup, it needs to spawn a separate process for efficient pipelining of USB communication, but such technical complexities shall be hidden inside the module so that it only exposes its high-level, user-friendly interface.

The problem is that the "guard" (and its indentation) had to be propagated into every Python executable that explicitly or implicitly used multiprocessing. Writing short Python scripts to automate laboratory tasks can be quite convenient even for non-programmers, but I cannot ask my fellow scientists to include this awkward, unpythonic feature into their every single script.

Below I suggest a solution as a first answer; I am looking forward to your alternatives and comments. Most importantly:

1. 
   Do you think this feature should once be added to the official multiprocessing module, too?
   
   
2. 
   If so, what's the canonical way to do it? If not, what should I do otherwise?)
   
   
3. 
   Do you think it's okay to link this solution in the numerous related questions on StackOverflow? It can help others, but I don't know the right policy regarding this.
   

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