How to close the ability to copy in pisa pdf Document
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I have a Django.
This my code

    template = get_template(template_src)
    context = Context(context_dict)
    html  = template.render(context)
    result = StringIO.StringIO()
    pdf = pisa.pisaDocument(StringIO.StringIO(html.encode("UTF-8")), result, encoding="utf-8")
    if not pdf.err:
        return HttpResponse(result.getvalue(), mimetype='application/pdf')
    return HttpResponse('We had some errors<pre>%s</pre>' % escape(html))


How to close the ability to copy in pisa pdf Document.