Pool within a Class in Python

You can also use multiprocessing with static functions in the class.

It looks like because of the way the function gets passed to the worker threads (pickling) you can't use instance methods unfortunately. My first thought was to use lambdas, but it turns out the built in pickler can't serialize those either. The solution, sadly, is just to use a function in the global namespace. As suggested in other answers, you can use static methods and pass self to make it look more like an instance method.

from multiprocessing import Pool
from itertools import repeat

class SeriesInstance(object):
    def __init__(self):
        self.numbers = [1,2,3]

    def run(self):
        p = Pool()
        squares = p.map(self.F, self.numbers)
        multiples = p.starmap(self.G, zip(repeat(self), [2, 5, 10]))
        return (squares, multiples)

    @staticmethod
    def F(x):
        return x * x

    @staticmethod
    def G(self, m):
        return [m *n for n in self.numbers]

if __name__ == '__main__':
    print(SeriesInstance().run())