import tkinter

root = tkinter.Tk()
root.geometry('300x340+500+200')
canvas = tkinter.Canvas(root, width=300, height=340, bg="lightblue")
canvas.place(x=0, y=0)
# ++++++++++++++++++++++++++++++++++++++++++++++++++++
def func():
    num = v.get()
    print("你选择了：",num)

v = tkinter.IntVar()
rb1 = tkinter.Radiobutton(root,text='体育',value=1,variable=v,command=func)
rb2 = tkinter.Radiobutton(root,text='美术',value=2,variable=v,command=func)
rb3 = tkinter.Radiobutton(root,text='音乐',value=3,variable=v,command=func)
rb4 = tkinter.Radiobutton(root,text='编程',value=4,variable=v,command=func)
# ++++++++++++++++++++++++++++++++++++++++
rb1.place(x=50,y=50)
rb2.place(x=50,y=100)
rb3.place(x=50,y=150)
rb4.place(x=50,y=200)
root.mainloop()