Tower of hanoi, index error

class HanoiT():

    def __init__(self, content=None):
        if content is None:
            self.content=[]
        else:
            self.content=content

    def addmethod(self, new_disk): #Add an element on the beginning of the list
        if new_disk <= self.content[0]:
            self.content.insert(0, new_disk)
        else:
            raise ValueError("No disk may be placed on top of a smaller disk")


    def deletemethod(self): #Delete the first element of a list
        self.content.pop(0)

    def affichage(self): #Method to print the list which represent the "disk" putted on the tower from the top to bottom
        for i in self.content:
            print(i, end=" ")

    def movedisk(self, Tsource, Ttarget): 
        Ttarget.addmethod(Tsource.content[0])
        Tsource.deletemethod()

    def movetower(self, N, Tour1, Tour3, Tour2):
        if N >= 1:
            self.movetower(N-1, Tour1, Tour2, Tour3)
            self.movedisk(Tour1, Tour3)
            self.movetower(N-1, Tour2, Tour3, Tour1)




N = 4
Tour1 = HanoiT([x for x in range(1, N+1)])
Tour1.affichage()
Tour2 = HanoiT([])
Tour3 = HanoiT([])
h = HanoiT()
h.movetower(N, Tour1, Tour2, Tour3)