>>> x = 37
>>> x
37
>>> y = 5
>>> print "x+y = ", x+y
x+y = 42
>>> side1 = 3.0
>>> side2 = 4.0
>>> import math
>>> # formula for getting the length of the opposing side 
>>> # of a right-angled triangle
>>> hypotenuse = math.sqrt(side1*side1+side2*side2)
>>> hypotenuse
5.0
>>> import math
>>> def hypotenuse(side1, side2):
      return math.sqrt(side1**2+side2**2) 
>>> # x**2 is shorthand for x*x
>>> hypotenuse(6.0,8.0)
10.0
>>> class hypotenuse:
      def __init__(self,side1,side2):
          self.sideA = side1
          self.sideB = side2
      def calculate(self):
         return math.sqrt(self.sideA**2+self.sideB**2)
>>> h = hypotenuse(6.0,8.0)
>>> h.calculate()
10.0
>>> # put the hypotenuse class into a separate module, 
>>> # as the file myhypotenuse.py
>>> import myhypotenuse
>>> h = myhypotenuse.hypotenuse(6.0,8.0)
>>> h.calculate()
10.0
>>> # now edit myhypotenuse in a text editor (changing 
>>> # the calculate function)
>>> # and reload the modified version
>>> reload(myhypotenuse)
<module `myhypotenuse' from `C:\pcupdate\myhypotenuse.py'>
>>> h2 = myhypotenuse.hypotenuse(6.0,8.0)
>>> h2.calculate()
hypotenuse : 10.0