想要创建2个按钮，一个开始语音识别，并保持打开状态，直到我单击按钮完成为止。问题是当我单击“开始”并且没有说停止时：

import tkinter as tk
import speech_recognition as sr

window = tk.Tk()
window.title("Voice to Text")
window.geometry("300x350")

def startvoice():
    r = sr.Recognizer()
    with sr.microphone() as source:
        print("speak now")
        audio = r.listen(source)
    try:
        startvoice.voice2text = r.recognize_google(audio)
        print("you said:{}".format(startvoice.voice2text))
    except:
        print("Your voice not clear")

def finished():
    text_field.focus()
    text_field.delete('1.0',tk.END)
    text_field.insert('1.0',startvoice.voice2text)

text_field = tk.Text(master=window,height=20,width=40)
text_field.grid(column=0,row=2)


button1 = tk.Button(text="Start",width=16,command=startvoice)
button1.grid(column=0,row=0)

button1 = tk.Button(text="finish",command=finished)
button1.grid(column=0,row=1)


window.mainloop()