class Global:
    killed = False

@app.route('/test1')
def test1():
    # Kill all other similar processes before running this process
    Global.killed = True
    time.sleep(1) # wait a while to be sure the other threads see that Global.killed ==True
    Global.killed = False

    # Run a mock process that takes some time
    a = 100
    while a >= 0:
        time.sleep(0.1)
        a -= 1
        print('koe', a)
        if Global.killed:
            print('killed!')
            break
    print('done!')

@app.route('/kill')
def kill():
    Global.killed = True
    return 'killed'