<>意思为缩进

def sv():

<>global isV

<>isV=True

><chv();

<>l1.config(font=("幼圆",18),fg="blue")

<>l1.place(x=160)

def sh():

<>global isV

<>isV=False

<>chv()

<>l1.config(font=("黑体",14),fg="red")

<>l1.place(x=0)

def chv():

<>st=""

<>if isV:

<><>for c in fu.get():

<><><>s+=c+'\n'

<><>ft.set(st)

<>else:

<><>ft.set(fu.get())