python写登陆窗口

import tkinter as tk
import tkinter.messagebox as msgbox
#
def btnok_click():
    if Entry1.get() == "xmq" and Entry2.get() == "1991":
    # 或者 if varname1.get() == "xmq" and varname2.get() == "1991":
        mainwin = tk.Tk()
        mainwin.title('Main windows')
        mainwin.geometry("350x200+300+200")
    else:
        msgbox.showinfo("警告","用户名或密码错误")

def btnreset_click():
    varname1.set("")
    varname2.set("")
#
loginwin = tk.Tk()
loginwin.title('Please Login')
loginwin.geometry("250x100+200+100")

# 创建用户名标签，label
labname1 = tk.Label(loginwin,text="用户名")
labname1.grid(row=0,column=0,ipadx=10,ipady=10)

# 创建单行输入框，entry
varname1 = tk.StringVar()
#变量与控件绑定的方式
Entry1 = tk.Entry(loginwin,textvariable=varname1)
Entry1.grid(row=0,column=1,columnspan=2)

# 创建密码标签，label
labname2 = tk.Label(loginwin,text="密码")
labname2.grid(row=1,column=0)

# 创建单行输入框，entry
varname2 = tk.StringVar()
Entry2 = tk.Entry(loginwin,show="*",textvariable=varname2)
Entry2.grid(row=1,column=1,columnspan=2)

# 创建登陆按钮
btn1 = tk.Button(loginwin,text="登陆",width=8,command=btnok_click)
btn1.grid(row=2,column=1)

# 创建重置按钮
btn1 = tk.Button(loginwin,text="重置",width=8,command=btnreset_click)
btn1.grid(row=2,column=2)

loginwin.mainloop()