import math

class Circle2:
   
   def __init__(self, radius=None, center_x=None, center_y=None):
      # Radius of the circle 
      if radius is None:
         self.__radius = 1.0	
      else:
         self.__radius = radius   
      
      # x coordinate of the center point
      if center_x	is None:
         self.__center_x = 0 
      else:
         self.__center_x = center_x
  
      # y coordinate of the center point
      if center_y is None:
         self.__center_y = 0
      else:
         self.__center_y = center_y 

   def getRadius(self):		# accessor method
      return self.__radius
  
   def getCenterX(self):		# accessor method
      return self.__center_x
  
   def getCenterY(self):	# accessor method
      return self.__center_y
  
  
   def setRadius(self, radius):	# mutator method
      # what possible error checking might be done here?
      self.__radius = radius
  

   def setCenter(self, center_x, center_y):	# mutator method
      self.__center_x = center_x
      self.__center_y = center_y
  

   # other methods
   def findArea(self):
      return (self.__radius * self.__radius * math.pi)
  

   def findCircumference(self):
      return (self.__radius * 2 * math.pi)
   
   def __str__(self):
      return "Radius: %.2f Coordinates (x, y): (%.2f, %.2f)" \
          % (self.__radius, self.__center_x, self.__center_y)
      
def main():
   circle1 = Circle2()
   circle2 = Circle2(2, 4, 5)
   
   print circle1
   print circle2

main()