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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 comment(request, template="generic/comments.html", extra_context=None):
 """ Handle a ``ThreadedCommentForm`` submission and redirect back to its related object. """

    response = initial_validation(request, "comment")
    if isinstance(response, HttpResponse):
        return response
    obj, post_data = response
    form_class = import_dotted_path(settings.COMMENT_FORM_CLASS)
    form = form_class(request, obj, post_data)
    if form.is_valid():
        url = obj.get_absolute_url()
        if is_spam(request, form, url):
            return redirect(url)
        comment = form.save(request)
        response = redirect(add_cache_bypass(comment.get_absolute_url()))
        # Store commenter's details in a cookie for 90 days.
        for field in ThreadedCommentForm.cookie_fields:
            cookie_name = ThreadedCommentForm.cookie_prefix + field
            cookie_value = post_data.get(field, "")
            set_cookie(response, cookie_name, cookie_value)
        return response
    elif request.is_ajax() and form.errors:
        return HttpResponse(dumps({"errors": form.errors}))
    # Show errors with stand-alone comment form.
    context = {"obj": obj, "posted_comment_form": form}
    context.update(extra_context or {})
    return TemplateResponse(request, template, context)