def i2():
    btn2['bg']='yellow'
def i3():
    btn3['bg']='yellow'
def i4():
    btn4['bg']='yellow'
def i5():
    btn5['bg']='yellow'
def i6():
    btn6['bg']='yellow'
def i7():
    btn7['bg']='yellow'
def i8():
    btn8['bg']='yellow'
def i9():
    btn9['bg']='yellow'
def i10():
    btn10['bg']='yellow'
def i11():
    btn11['bg']='yellow'
def i12():
    btn12['bg']='yellow'
I've been thinking about this issue for a long time how I can this statement short? plz help me..
