Just consider a very simple example, as follows:

1. Import the relevant library first:

import multiprocessing

2. Then, define a subclass, MyProcess, overriding only the run method, which returns the process' name:

class MyProcess(multiprocessing.Process):

    def run(self):
        print ('called run method by %s' %self.name)
        return

3. In the main program, we define a subclass of 10 processes:

if __name__ == '__main__':
    for i in range(10):
        process = MyProcess()
        process.start()
        process.join()