Random Ergodic Graph

def genererWeb(n):
    if n < 3:
        throw BaseException("Taille de web invalide!")

    web = SimpleWeb(n)

    def arc(x,y):
        try :
            web.addArc(x,y)
        except BaseException:
            None

    nbNoeuds = 1
    isset    = {k:False for k in range(n)}

    premier = int(random()*n)
    isset[premier] = True

    current = premier
    while nbNoeuds < n:

        noeud = int(random()*n)
        while noeud == current:
            noeud = int(random()*n)

        if not isset[noeud]:
            isset[noeud] = True
            nbNoeuds += 1

        arc(current, noeud)
        current = noeud

    if current != premier:
        arc(current, premier)

    arc(0,1)
    arc(1,0)
    arc(2,0)
    arc(1,2)