import time

class SalesManager:

def work(self):

print("Sales Manager working...")

def talk(self):

print("Sales Manager ready to talk")

class Proxy:

def __init__(self):

self.busy = 'No'

self.sales = None

def work (self):

print("Proxy checking for Sales Manager availability")

if self.busy == 'No':

self.sales = SalesManager()

time.sleep(2);

self.sales.talk()

else:

time.sleep(2);

print("Sales Manager is busy")

if __name__ == '__main__':

p = Proxy()

p.work()

p.busy = 'Yes'

p.work()