ttk.Combobox types as none

Python Help
1

‘’'python

ttk.Label(frame, text = 'TL').grid(column = 7, row = 0)
tech_level = IntVar()
tech_combo = ttk.Combobox(frame, textvariable = tech_level,
                          values = (7, 8, 9, 10, 11,
                                    12, 13, 14, 15),
                          state = "readonly").grid(column = 8, row = 0)
tech_combo.bind('<<ComboboxSelected>>', tech_effect)

‘’’
Throws this error:

‘’'python

Traceback (most recent call last):
  File "C:\Users\daves\AppData\Local\Programs\Python\Python312\MyPythonPrograms\Book5tkimp.py", line 95, in <module>
    tech_combo.bind('<<ComboboxSelected>>', tech_effect)
AttributeError: 'NoneType' object has no attribute 'bind'

‘’’

What am I doing wrong?

2

See python - Why do I get "AttributeError: NoneType object has no attribute" using Tkinter? Where did the None value come from? - Stack Overflow

3

Thanks a bunch.