Accessing Children in LabelFrames using Tkinter and Python 3 - python-3.x

Question

I am working with tkinter and have set up a bare bones application of my project. My objective is to retrieve a value from tk.Entry() which lies within a tk.LabelFrame() (in this code referenced by the groupbox variable). The button finds the groupbox, and the code passes the compiler, too. I guess my question is: How do I access Widgets and their values in a LabelFrame?
#!/usr/bin/env python
# -*- coding: utf-8 -*-
import tkinter as tk
class Application(tk.Frame):
def __init__(self, master=None):
tk.Frame.__init__(self, master)
self.master.title("Application Title")
# Introduce LabelFrame
self.groupbox = tk.LabelFrame(self, text="Parameters")
self.groupbox.grid(row=0, column=1, padx=5, pady=5)
# Test Label & Entry Widget
label = tk.Label(self.groupbox, text="label=")
label.grid(row=0, column=0, sticky="W")
entry = tk.Entry(self.groupbox)
entry.insert(0, default_value)
entry.grid(row = 0, column=1)
# Compile Button
button = tk.Button(self.groupbox, text="Compile", command=self.compile)
button.grid(row=1, column=1)
# Retrieve first Value (second Widget) from LabelFrame
def compile(self):
print(self.groupbox.entry.get(1))
if __name__ == '__main__':
figure = Application()
figure.pack()
figure.mainloop()
I am doing this because I want to perform some calculations based on the tk.Entry() values triggered by a button click which is contained in the same LabelFrame() as suggested by the code snippet above (in the original code there are a lot more widgets but that's essentially the gist of my current problem).

Answer 1

Change entry to self.entry.
class Application(tk.Frame):
def __init__(self, master=None):
....
self.entry = tk.Entry(self.groupbox)
self.entry.insert(0, "default_value")
self.entry.grid(row = 0, column=1)
...
# Retrieve first Value (second Widget) from LabelFrame
def compile(self):
print(self.entry.get())