Debugging RadioButtons program in Python

I wrote a simple program importing Tkinter just to play with Radio Buttons. I find that I'm getting errors in very, very weird places.

 from Tkinter import *

class Application (Frame):
    def __init__(self, master):
        Frame.__init__(self, master)
        self.grid()
        self.create_widgets()

    def create_widgets(self):


        Label(self, text = "Select the last book you read.").grid (row = 0, column = 0, sticky = W)

        self.choice = StringVar() 

        Radiobutton (self,text = "Nausea by Jean-Paul Sartre",variable = self.choice,
                 value = "Wake up. This is a dream. This is all only a test of the emergency broadcasting system.",
                 command = self.update_text).grid (row = 2, column = 1, sticky = W)

        Radiobutton (self,
                 text = "Infinite Jest by David Foster Wallace",
                 variable = self.choice,
                 value = "Because an adult borne without the volition to choose the thoughts that he thinks, is going to get hosed ;)",
                 command = self.update_text).grid (row = 3, column = 1, sticky = W)

        Radiobutton (self,
                 text = "Cat's Cradle by Kurt Vonnegut",
                 variable = self.choice,
                 value = " \"Here we are, trapped in the amber of the moment. There is no why!\" ",
                 command = self.update_text.grid (row = 4, column = 1, sticky = W)

        self.开发者_JS百科txt_display = Text (self, width = 40, height = 5, wrap = WORD)
        self.txt_display.grid (row = 6, column = 0, sticky = W)


    #There is only one choice value - self.choice. That can be "printed."

    def update_text(self):
        message = self.choice.get()
        self.txt_display.delete (0.0, END)
        self.txt_display.insert (0.0, message)

# The Main
root = Tk()
root.title ("The Book Critic One")
root.geometry ("400x400")

app = Application (root)
root.mainloop()

I seem to be getting errors in very odd places. One came in the "=" sign in the Label attribution and when I changed it to == when i was playing around, the next one came in the variable part of the RadioButton attributes.

Any help would be greatly appreciated. Won't be able to respond immediately as I have to leave to work in a bit, but if you do spot where the bugs are, please let me know.

There are a lot of things going on here. I'll just point out the few that I've found quickly looking at this.

For your Label you shouldn't have = before your parameters...

Label = (self, text = "Select the last book you read.").grid (row = 0, column = 0, sticky = W)

to:

Label(self, text = "Select the last book you read.").grid (row = 0, column = 0, sticky = W)

Change all instances of RadioButton to Radiobutton as that is the actual name of the class in Tkinter.

choice1, choice2, and choice3 do not exist in Application.

More Stuff:

def create_widgets() is missing the self parameter: def create_widgets(self)

Your update_text() function isn't working because you're referencing self.text_display, I believe you want this to be self.txt_display since that is how you defined it previously.