key = 0
def gen_dot(T):
    global key


    def atnode(n, parent):
        global key
        key += 1
        atn = anytree.Node(str(key),parent = parent, display_name = str(n))
        if n.type == 1:
            sub1 = atnode(n.sub1,atn)
        if n.type == 2:
            sub1 = atnode(n.sub1,atn)
            sub2 = atnode(n.sub2,atn)
        return atn

    root = atnode(T,None)


    DotExporter(root,
                nodeattrfunc=lambda node: 'label="{}"'.format(node.display_name)).to_dotfile("graph.txt")
    DotExporter(root,
                nodeattrfunc=lambda node: 'label="{}"'.format(node.display_name)).to_picture("graph.png")