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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 admin_tools_render_menu_item(context, item, index=None):
 """ Template tag that renders a given menu item, it takes a ``MenuItem`` instance as unique parameter. """

    item.init_with_context(context)

    context.update({
        'template': item.template,
        'item': item,
        'index': index,
        'selected': item.is_selected(context['request']),
        'admin_url': reverse('%s:index' % get_admin_site_name(context)),
    })
    return context