Using python multiprocessing Pool in the terminal and in code modules for Django or Flask

Question

When using multiprocessing.Pool in python with the following code, there is some bizarre behavior.

from multiprocessing import Pool
p = Pool(3)
def f(x): ret         


        

Answer 1

There is another possible source for this error. I got this error when running the example code.

The source was that despite having installed multiprosessing correctly, the C++ compiler was not installed on my system, something pip informed me of when trying to update multiprocessing. So It might be worth checking that the compiler is installed.