#!/usr/bin/python

class Calculator:

	def __init__(self, ina, inb):
		self.a = ina
		self.b = inb

	def add(self):
		return self.a + self.b

	def mul(self):
		return self.a * self.b

class Scientific(Calculator):

	def power(self):
		return pow(self.a, self.b)

newCalculation = Calculator(10, 20)

print 'a + b: %d' % newCalculation.add()
print 'a * b: %d' % newCalculation.mul()

newPower = Scientific(2, 3)

print 'a + b: %d' % newPower.add()
print 'a * b: %d' % newPower.mul()
print 'a power b: %d' % newPower.power()
