import numpy as np
import psutil, gc, os

n = 100001

def _test_fill(z):
    arrays = [z+z, z+z]
    arrays3 = np.empty((len(arrays), len(arrays[0])), dtype='int64')
    for i in range(len(arrays)):
        row = arrays[i]
        for j in range(len(arrays[0])):
            arrays3[i,j] = row[j]
            pass

def get_process():
    pid = os.getpid()
    return psutil.Process(pid)

_TWO_20 = float(2 ** 20)

def get_lost(f):
    process = get_process()
    z = range(n)
    befor_mem = process.memory_info()[0] / _TWO_20
    f(z)
    for i in range(20):
        gc.collect()
    after_mem = process.memory_info()[0] / _TWO_20
    return after_mem - befor_mem
        
def test_lost():
    lost = get_lost(_test_fill)
    assert lost < 5, 'expected to lose less than 5, lost %d' % int(lost)

if __name__ == '__main__':
    test_lost()