I would like to ask you about multiprocessing for simple calculation in Python

The code below is a summary (?) of the questions.

Although oversimplified in the code below, the resulting matrix M approached by each process is located in a different position (each process wants to write a value to a different M [row] [column].)

By copying the variable M from the process? The value of the matrix element does not change as the id(M) value is taken differently. I tried to declare it as a global variable, but it didn't work outㅠㅜ I reserved how to use queue because it was too slow.

Processes can take the memory address of the global variable as it is Or is there any other way to get the results...?

Thank you.

from multiprocessing import Process
import numpy

def main():
    mother()

def mother():
    PROCESS_NUM = 4

    M = numpy.array(3) # Variable to write output
    element = [30, 40, 50, 60]

    for i in range(3):
        PROCESS_LIST = []

        for i in range(PROCESS_NUM):
            p = Process(target = pF_mother,  args = (
                    element[i], M,))
            PROCESS_LIST.append(p)
            PROCESS_LIST[i].start()

        for i in range(PROCESS_NUM):
            PROCESS_LIST[i].join()

    return M

def pF_mother(elt, output):
    output = elt

    return output

if __name__ == "__main__":
    main()