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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def flag(request, comment_id, next=None):
 """ Flags a comment. Confirmation on GET, action on POST. Templates: :template:`comments/flag.html`, Context: comment the flagged `comments.comment` object """

    comment = get_object_or_404(comments.get_model(), pk=comment_id, site__pk=settings.SITE_ID)

    # Flag on POST
    if request.method == 'POST':
        perform_flag(request, comment)
        return next_redirect(request, fallback=next or 'comments-flag-done',
            c=comment.pk)

    # Render a form on GET
    else:
        return render_to_response('comments/flag.html',
            {'comment': comment, "next": next},
            template.RequestContext(request)
        )