Why I am getting AttributeError: "'NoneType' object has no attribute 'get'" with Python and Tkinkter?

from tkinter import *

app=Tk()

app.title(" BRAIN SYNCRONIZATION SOFTWARE ")

e1=Entry(app).pack()
t1=Text(ap开发者_JAVA技巧p).pack()

def InputFun():
        file=open("acad.txt","a")
        file.write("%s;%s"%(t1.get("0.1",END),e1.get()))
        file.close()
b1=Button(app,text="INPUT",command=InputFun,height=3,width=4).pack(side=LEFT,padx=30,pady=30)

This is the code I wrote, but I am repeatedly getting the following error when I press the input button:

Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Python31\lib\tkinter\__init__.py", line 1399, in __call__
    return self.func(*args)
  File "C:\Users\vonn\Desktop\brain syncronization.py", line 15, in InputFun
    file.write("%s"%t1.get("0.1",END))
AttributeError: 'NoneType' object has no attribute 'get'

Why is it not writing the file?

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t1=Text(app).pack()

should be

t1=Text(app)
t1.pack()

The Tkinkter pack() method returns None, you can't run .get() on it, but need to keep t1 referring to the text object itself.

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I don't think that Entry(app).pack() will return anything. Do you mean e1=Entry(app); e1.pack()?