I want save form data before submit to action url in flask

```
<form action="" method="POST">
    <input type="hidden" name="PAYEE_ACCOUNT" value="U1234567">
    <input type="hidden" name="PAYEE_NAME" value="Name">
    <input type="text"   name="PAYMENT_AMOUNT">
    <input type="submit" name="PAYMENT_METHOD" />
</form>

```

I can submit this form, but i want save form data before submit

View:

```
@mod.route('/payment/', methods=['GET', 'POST'])
def payment():
    if request.method != "POST":
        return render_template('form.html')

    form = request.form

    form_data = {'PAYEE_ACCOUNT': form['PAYEE_ACCOUNT'],
                 'PAYEE_NAME': form['PAYEE_Name'],
                 'PAYMENT_AMOUNT' : form['PAYMENT_AMOUNT']
                 }

    # Save Data

    import urllib
    params = urllib.urlencode(form_data)

    url = 'http://www.example.com'
    return redirect(url, params)

```

Please help me