class tree:
    def __init__(self , liste):
        self.racine = liste[0].data
        self.noeud = liste[1:]

A = node("A" , None , None)
B = node("B" , "A" , "Gauche")
C = node("C" , "A" , "Droit")
D = node("D" , "B" , "Gauche")
E = node("E" , "B" , "Droit")
F = node("F" , "C" , "Droit")
G = node("G" , "E" , "Gauche")
H = node("H" , "E" , "Droit")
I = node("I" , "F" , "Gauche")

arbre = tree([A,B,C,D,E,F,G,H,I])

print( arbre.noeud[2].data ,
        "est le fils" ,
        arbre.noeud[2].position ,
        "de" , arbre.noeud[2].parent)