太简单了，让它复杂一点，让它变成一个应用程序

如果你想将上述MD5校验工具转变为一个完整的应用程序，比如Windows桌面应用，你可以考虑使用Python的Tkinter库来构建用户界面。以下是基本框架：

import tkinter as tk
from tkinter import filedialog
import hashlib

class MD5CheckerApp(tk.Tk):
    def __init__(self):
        super().__init__()
        
        self.title("MD5 Checksum Utility")
        self.geometry('400x200')

        self.file_label = tk.Label(self, text="Select a file:")
        self.file_label.pack()

        self.select_button = tk.Button(self, text="Browse", command=self.open_file)
        self.select_button.pack(pady=10)

        self.check_result_var = tk.StringVar()
        self.result_label = tk.Label(self, textvariable=self.check_result_var)
        self.result_label.pack()

    def open_file(self):
        file_path = filedialog.askopenfilename()
        if file_path:
            checksum = self.calculate_md5(file_path)
            self.check_result_var.set(f"File: {file_path}\nChecksum: {checksum}")

    def calculate_md5(self, file_path):
        with open(file_path, 'rb') as f:
            md5 = hashlib.md5()
            while chunk := f.read(8192):
                md5.update(chunk)
            return md5.hexdigest()

if __name__ == "__main__":
    app = MD5CheckerApp()
    app.mainloop()