主函数while循环中第一行“with concurrent.futures...”的ThreadPoolExecutor Attribute error: __enter__出现问题。这是我第一次尝试这种线程化方式，所以我不确定问题出在哪里。

#Sets up to 25 sectors as R or Y
def crop_dehydration(plot):
    for _ in range(25):
        x = random.randint(0,9)
        y = random.randint(0,9)
        if plot[x][y] != 'G':
            plot[x][y].data = random.choice(hydration_choices)

#create irrigation logic

#Scans farm for R and Y sectors to add them to independent 
#shceduled irrigation lists
def scan_farm(plot):
    for i in range(10):
        for j in range(10):
            if plot[i][j] == 'R':
                R.append(plot[i][j])
            if plot[i][j] == 'Y':
                Y.append(plot[i][j])

#handler for R and Y groups
def irrigate_sector(group, secs):

    #irrigation handler for sectors within R and Y groups
    def irrigate(sector, secs):
        time.sleep(secs)
        sector = 'G'
        return sector

    with concurrent.futures.ThreadPoolExecutor as executor:
        results = {executor.submit(irrigate,sector, secs) for sector in group}
        for i in concurrent.futures.as_completed(results):
            return i.result()

def main():
    farm = Sector()
    while(True):
        farm.display()
        crop_dehydration(farm.plot)
        scan_farm(farm.plot)

        with concurrent.futures.ThreadPoolExecutor as executor:
            r_thread = executor.submit(irrigate_sector, R, 25)
            return r_thread.results()
        with concurrent.futures.ThreadPoolExecutor as executor:
            y_thread = executor.submit(irrigate_sector, Y, 10)
            return y_thread.results()
        
main()


#create app initializer
#display gui