11_4.py

# coding=utf-8
#!/usr/bin/python

class Person:
	'''Represents a person.'''
	population = 1
	def __init__(self, name):
		'''Initializes the person's data.'''
		self.name = name
		print '(Initializing %s)' % self.name
# When this person is created, he/she
# adds to the population
		Person.population += 1

	def __del__(self):
		'''I am dying.'''
		print '%s says bye.' % self.name
		Person.population -= 1
		if Person.population == 0:
			print 'I am the last one.'
		else:
			print 'There are still %d people left.' % Person.population

	def sayHi(self):
		'''Greeting by the person.
		Really, that's all it does.'''
		print 'Hi, my name is %s.' % self.name

	def howMany(self):
		'''Prints the current population.'''
		if Person.population == 1:
			print 'I am the only person here.'
		else:
			print 'We have %d persons here.' % Person.population

swaroop = Person('Swaroop')
swaroop.sayHi()
swaroop.howMany()
kalam = Person('Abdul Kalam')
kalam.sayHi()
kalam.howMany()
swaroop.sayHi()
swaroop.howMany()