class Person:
	def __init__(self, ln, fn, t):
		self.lastName=ln
		self.firstName = fn
		self.title=t 
		self.introStrategy=BriefIntro()

	def hi(self):
		return self.introStrategy.introduce(self)

	def setIntroStrategy(self, strategy):
		self.introStrategy=strategy

class IntroductionStrategy(object):
	def introduce(self, person):
		return "Hi, I am "

class BriefIntro(IntroductionStrategy):
	def introduce(self, person):
		return super(BriefIntro, self).introduce(person)+person.firstName

class TypicalIntro(IntroductionStrategy):
	def introduce(self, person):
		return super(TypicalIntro, self).introduce(person)+person.title+" "+person.firstName+" "+person.lastName

arnold=Person("Rosenbloom", "Arnold", "Lecturer")
sid=Person("Smith", "Sid", "Dr.")

print arnold.hi()
print sid.hi()
arnold.setIntroStrategy(TypicalIntro())
print arnold.hi()
print sid.hi()
sid.setIntroStrategy(TypicalIntro())
print arnold.hi()
print sid.hi()