Print in Order.py

import threading

class Foo:
    def __init__(self):
		# create lock to control sequence between first and second functions
        self.lock1 = threading.Lock()
		self.lock1.acquire()
		
		# create another lock to control sequence between second and third functions
        self.lock2 = threading.Lock()
        self.lock2.acquire()

    def first(self, printFirst: 'Callable[[], None]') -> None:
        printFirst()
		
		# since second function is waiting for the lock1, let's release it
        self.lock1.release()

    def second(self, printSecond: 'Callable[[], None]') -> None:
		# wait for first funtion to finish
        self.lock1.acquire()
        
		printSecond()
		
		# let's release lock2, so third function can run
        self.lock2.release()

    def third(self, printThird: 'Callable[[], None]') -> None:
		# wait for second funtion to finish
        self.lock2.acquire()
		
        printThird()