my_coroutine_in_py_27.py

from collections import namedtuple

ALIVE = '*'
EMPTY = '-'
Query = namedtuple('Query',('y','x'))
Transition = namedtuple('Transition', ('y', 'x', 'state'))
TICK = object()

class MyReturn(Exception):
    def __init__(self, value):
        self.value = value

def count_neighbors(y, x):
    n_ = yield Query(y + 1, x + 0)
    ne = yield Query(y + 1, x + 1)
    e_ = yield Query(y + 0, x + 1)
    se = yield Query(y - 1, x + 1)
    s_ = yield Query(y - 1, x + 0)
    sw = yield Query(y - 1, x - 1)
    w_ = yield Query(y + 0, x - 1)
    nw = yield Query(y + 1, x - 1)
    neighbor_state = [ n_, ne, e_, se, s_, sw, w_, nw]
    count = 0
    for state in neighbor_state:
        if state == ALIVE:
            count += 1
    raise MyReturn(count)

def step_cell(y, x):
    state = yield Query(y, x)

    #neighbors = yield from count_neighbors(y, x)
    it = count_neighbors(y, x)
    try:
        value = next(it)
        while True:
            value = it.send((yield value))
    except MyReturn as e:
        neighbors = e.value

    print('Count: ', neighbors)
    next_state = game_logic(state, neighbors)
    yield Transition(y, x, next_state)

def game_logic(state, neighbors):
    if state == ALIVE:
        if neighbors < 2:
            return EMPTY
        elif neighbors > 3:
            return EMPTY
    else:
        if neighbors == 3:
            return ALIVE
    return state


it = step_cell(10, 5)
q0 = next(it)
print('Me: ', q0)
q1 = it.send(ALIVE)
print('First yield: ', q1)
q2 = it.send(ALIVE)
print('Second yield: ', q2)
q3 = it.send(ALIVE)
print('Third yield: ', q3)
q4 = it.send(EMPTY)
print('Forth yield: ', q4)
q5 = it.send(EMPTY)
print('Fifth yield: ', q5)
q6 = it.send(EMPTY)
print('Sixth yield: ', q6)
q7 = it.send(EMPTY)
print('Seventh yield: ', q7)
q8 = it.send(EMPTY)
print('Eight yield: ', q8)
t1 = it.send(EMPTY)
print('Outcome: ', t1)