我对 Flask 处于初学者水平，正在尝试创建一个网络应用程序。用户将从文件资源管理器上传照片，图像将显示在屏幕上（感谢我在这里找到的答案）。我的问题是，当我在确认页面单击“返回”时，我想重定向到文件上传页面（http://127.0.0.1:5000/upload），但它似乎根本不起作用。网址发生变化，但页面仍处于 /uploadconfirmation 页面，询问用户是否要继续。我不确定这是否是由于我发现显示图像的代码所致。任何帮助表示赞赏！图片：代码：main.pyimport osfrom flask import Flask, flash, request, redirect, url_for, render_template, send_from_directoryfrom werkzeug.utils import secure_filenameUPLOAD_FOLDER = 'C:/Users/yurik/OneDrive/FYPCode/code+images/FullProject/imagesUploaded'ALLOWED_EXTENSIONS = set(['png', 'jpg', 'jpeg', 'gif'])app = Flask(__name__)app.secret_key = "secret key"app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER# specifies max file size = 16MBapp.config['MAX_CONTENT_LENGTH'] = 16 * 1024 * 1024def allowed_file(filename):    return '.' in filename and filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS# HOME:#index method,returns index.html@app.route('/home')def index():                                 return render_template('index.html')# UPLOAD FILE:  @app.route('/upload')def upload_page():    return render_template('upload.html')@app.route('/', methods=['POST'])def upload_file():    if request.method == 'POST':        # check if the post request has the file part        if 'file' not in request.files:            flash('No file part')            return redirect(request.url)        file = request.files['file']        if file.filename == '':            flash('No file selected for uploading')            return redirect(request.url)        # file is uploaded to imagesUploaded folder in FullProject        if file and allowed_file(file.filename):            filename = secure_filename(file.filename)            file.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))            return redirect(url_for('file_confirm', filename=filename))        else:            flash('Allowed file types are png, jpg, jpeg, gif')            return redirect(request.url)