ajax如何与python一起使用？ [关闭]

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            <div class="grid--cell mb0 mt8">Closed <span title="2012-12-02 20:13:48Z" class="relativetime">7 years ago</span>.</div>
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I'm been googling around, but I don't quite understand how ajax works. Could please somebody explain how this works?

$.ajax({
        url: "{{ url_for( 'app.slideshow.<tag>' ) }}",
        type: "",
        data: {'param':},
        dataType: "",
        success : function(response)
        {
        }

What I'm trying to do is see if document.getElementsByClassName(current) has changed. If it has, it will ask app.py for comments and tags on current, and update the page without refreshing. I have no idea what to write to receive this on the app.py either.

I'll include my app.py, but it is not good.

from flask import Flask,session,url_for,request,redirect,render_template
import api,db   
app = Flask(__name__)
#app.secret_key = "secret"

@app.route('/slideshow/<tag>', methods=['GET', 'POST'])
def slide():
if request.method=="GET":
    pic = request.get('current').href
    taglist = db.getTaglist()
    tags = db.getTags(pic)
    piclist = db.getPics(<tag>)
    commentlist = db.getComments(pic)
    return render_template("slide.html", taglist = taglist, tags =tags, piclist =piclist, commentlist = commentlist, url = url)
else:   
    button = request.form['button']
    pic = request.get('current').href

    if button=="submit":
        aComment = request.form['comment']
        db.addComment(pic,aComment)
    elif button == "submitnewtag":
        if request.form['Addnewtag']
            aTag = request.form['Addnewtag']
            db.addTag(pic,aTag)
        else:
            aTag =  request.form['select1']
            db.addTag(pic,aTag)


if __name__=="__main__":
    app.debug=True
    app.run(port=5300)

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