How to change widget's state with checkbutton

checkbutton.py

import ctypes
import tkinter

#Function when checkbutton clicked
def change_button_state():
    if var.get():
        b["state"] = "disable"  #disable
    else:
        b["state"] = "active"   #activate


if __name__ == "__main__":
    ctypes.windll.shcore.SetProcessDpiAwareness(1)
    root = tkinter.Tk()
    
    b = tkinter.Button(
        root,
        text="button",
        width=15,
        )
    b.pack()
    
    var = tkinter.BooleanVar(root)
    check = tkinter.Checkbutton(
        root,
        text="disable button",
        variable=var,               #set variable
        command=change_button_state,
        )
    check.pack()
    root.mainloop()