>>> a=Polygone()
>>> a.add(5,3)
>>> a.add(5,9)
>>> a
[ <__main__.Point instance at 0x011F0558>,<__main__.Point instance at 0x011E8F30>]

# -*- coding: latin-1 -*-

class Point:
    def __init__(self,x,y):
        self.coords = (x, y)
        self.next = None
    
    def getData(self):
        return self.coords
    
    def getNext(self):
        return self.next
    
    def setData(self,newdata):
        self.coords = newdata
    
    def setNext(self,newnext):
        self.next = newnext


class Polygone:
    def __init__(self):
        self.head = Point(-1,-1)
        self.head.setNext(self.head)
        
    def isEmpty(self):
        return self.head.getNext() == self.head
    
    def add(self,x,y):
        temp = Point(x,y)
        temp.setNext(self.head.getNext())
        self.head.setNext(temp)
    
    def addAfter(self,x,y,q,z):
        current = self.head.getNext()
        temp = Point(q,z)
        temp.setNext(current.getNext())
        current.setNext(temp)
    
    def length(self):
        current = self.head.getNext()
        count = 0
        res=""
        while current != self.head:
            count = count + 1
            current = current.getNext()
        res += 'Votre polygone a '+str(count)+' points'
        return res
    
    def search(self,x,y):
        current = self.head.getNext()
        found = False
        while current != self.head and not found:
            if current.getData() == (x,y):
                found = True
            else:
                current = current.getNext()
        return found
    
    def remove(self,x,y):
        previous = self.head
        current = self.head.getNext()
        found = False
        while current != self.head and not found:
            if current.getData() == (x,y):
                found = True
            else:
                previous = current
                current = current.getNext()
        if found:
                previous.setNext(current.getNext())
                
    def removeLast(self):
        previous = self.head
        current = self.head.getNext()
        previous.setNext(current.getNext())    

        
    def __repr__(self):
        current = self.head.getNext()
        res = "[ "
        while( current != self.head ):
            res += str(current)
            current = current.getNext()
        res+="]"
        return res

res += '(x: %d, y: %d), ' % current.getData()

>>> a=Polygone()
>>> a.add(1,1)
>>> a.add(2,2)
>>> a.add(2,5)
>>> a
[(x: 2, y: 5),(x: 2, y: 2),(x: 1, y: 1),]

class Point(object):
    __slots__ = ['coords']

    def __init__(self, x, y):
        self.coords = (x, y)


class Polygone(object):
    def __init__(self):
        self._points = []

    def isEmpty(self):
        return (len(self._points) == 0)

    def add(self, x, y):
        self._points.append(Point(x, y))

    def addAfter(self, x, y, q, z):
        # Не знаю зачем тут x, y - оставил для совместимости ))
        self._points.insert(0, Point(q, z))

    def length(self):
        return 'Votre polygone a %d points' % len(self._points)

    def search(self, x, y):
        found = filter(lambda pt, coords=(x, y): pt.coords == coords, self._points)
        return bool(found)

    def remove(self, x, y):
        self._points = filter(lambda pt, coords=(x, y): pt.coords != coords, self._points)

    def removeLast(self):
        self._points.pop()

    def __repr__(self):
        return '[%s]' % ', '.join(map(lambda pt: '(x: %d, y: %d)' % pt.coords, self._points))