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cmsplugin_comments / forms.py

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from django import forms
from django.contrib.comments.forms import CommentForm
from captcha.fields import CaptchaField
from django.utils.translation import ugettext as _

class CommentFormWithCaptcha(CommentForm):
    captcha = CaptchaField()
    url = 1

    def get_comment_create_data(self):
        return super(CommentFormWithCaptcha, self).get_comment_create_data()