import tkinter
import tkinter.messagebox
root = tkinter.Tk()
root.title('BMI的测试')
bmi=tkinter.StringVar()
Label = tkinter.Label(root,text="身高")
Label.place(x=20,y=10,width=30,height=20)
Label=tkinter.Label(root,text="m")
Label.place(x=90,y=10,width=30,height=