Python 3.4 Tkinter - Object has no attribute -

i'm making program kind of simulate console. code far (i started today, learning tkinter, although i'm not sure if tkinter best choice):

from tkinter import *  class app:     def __init__(self, master):         self.frame = frame(master, bg = 'black')         self.bottomframe = frame(master, bg = 'black')         self.elabel = label(master, text = '>', bg = 'black', font = 'system', fg = 'white')         self.einput = entry(master, bd =0, bg = 'black', font = 'system', fg = 'white', command = self.update_text())          # packing         self.frame.pack()         self.bottomframe.pack(side = bottom)         self.elabel.pack(side = left)         self.einput.pack(side = left)     def update_text(self):         self.einput.insert(0, '>')   root = tk() app = app(root) root.mainloop() 

the error is

traceback (most recent call last):   file "c:/users/*/pycharmprojects/consoledungeon/game.py", line 21, in <module>     app = game(root)   file "c:/users/*/pycharmprojects/consoledungeon/game.py", line 9, in __init__     self.einput = entry(master, bd =0, bg = 'black', font = 'system', fg = 'white', command = self.update_text())   file "c:/users/*/pycharmprojects/consoledungeon/game.py", line 17, in update_text     self.einput.insert(0, '>') attributeerror: 'game' object has no attribute 'einput' 

and 1 more thing: in line

self.einput = entry(master, bd =0, bg = 'black', font = 'system', fg = 'white', command = self.update_text()) 

i wasn't sure how use command argument.

i'm not sure command argument supposed on entry widget, that's problem lives alright. command expects callable (that is, function name, not calling of function). way program flows right is:

create app make app.frame make app.bottomframe make app.elabel make app.einput --> oh, there's function call in declaration, gotta follow before     finish making object ------> function call refers `app.einput`, don't have 1 of         (yet!) better throw attributeerror