При вызове функции go(), выдаёт ошибку: TypeError: go() missing 1 required positional argument: 'root'

From tkinter import *
from tkinter import ttk
from tkinter.ttk import Combobox
import sqlite3

class GOODZONE():

     def __init__(self,root):
     #denote root
     self.root = root

     #create window
     root.title("file")
     root.geometry('100x100')

     self.btn = Button(root,text = "submit", command = self.go)
     self.btn.grid(column = 0, row = 0)

     #cool func
     def go(self, root):
     print("Hello World")

root = Tk()
good = GOODZONE(root)
root.mainloop()