Tkinter object scope

[riversr54]

Thank you so much for the very quick reply. As soon as I saw it, I knew, "I should have thought of that", but I didn't Now to the bad news...
I made those changes but still have the same problem.

The error is:

  File "D:\Projects\Pycharm\DSAFinalProject\EnterBook.py", line 27, in SaveBook
    book = Book(self.entBookTitle.get(), self.entBookISBN.get(), self.entBookAuthor.get(), self.entBookYear.get())
                ^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'get'

What am I missing?


My updated code:

from tkinter import *
from tkinter import ttk
from Book import *

class EnterBookWindow(Toplevel):

    def __init__(self):
        Toplevel.__init__(self)
        self.title("Enter a Book in xx Data Structure")
        self.geometry('400x400')
        frameLeft = Frame(self, width=40, padx=20, pady=20)
        frameLeft.pack(side=LEFT)
        frameRight = Frame(self, width=40, padx=20, pady=20)
        frameRight.pack(side=RIGHT)

        lblTitle = ttk.Label(frameRight, text="Title:").pack(padx=10, pady=0)
        self.entBookTitle = ttk.Entry(frameRight, font=('Helvetica', 12), width=20).pack(padx=10, pady=10)
        lblISBN = ttk.Label(frameRight, text="ISBN:").pack(padx=10, pady=0)
        self.entBookISBN = ttk.Entry(frameRight, font=('Helvetica', 12), width=20).pack(padx=10, pady=10)
        lblAuthor = ttk.Label(frameRight, text="Author:").pack(padx=10, pady=0)
        self.entBookAuthor = ttk.Entry(frameRight, font=('Helvetica', 12), width=20).pack(padx=10, pady=10)
        lblYear = ttk.Label(frameRight, text="Year:").pack(padx=10, pady=0)
        self.entBookYear = ttk.Entry(frameRight, font=('Helvetica', 12), width=20).pack(padx=10, pady=10)
        btnSave = ttk.Button(frameRight, text="Save Data", command=self.SaveBook).pack(padx=20, pady=10)

    def SaveBook(self):
        book = Book(self.entBookTitle.get(), self.entBookISBN.get(), self.entBookAuthor.get(), self.entBookYear.get())