用Flask提交图片

Question

我试图修改我的html页面已经包含使用flaks和python3的文本和图片，但它不能使用？我可以提一些建议吗？

@app.route('/modify/>', methods=['GET', 'POST'])
def modify(id):
data = Datacontent.query.filter_by(id=id).first()
if request.method == 'POST':
    try:        
        title = request.form['title']
        content = request.form['content']
        picture = request.files['picture']

        data.title = title
        data.content = content
        data.picture = picture
        db.session.commit()
        return redirect(url_for('main', id=id))
    except:
        return redirect(url_for('main', id=id))
else:
    return render_template('modify.html', data=data)