def render_content(article, content_attr='content', markup_attr='markup'):
    """ Display an the body of an article, rendered with the right markup.

    - content_attr is the article attribute that will be rendered.
    - markup_attr is the article atribure with the markup that used
      on the article. the choices are:
      - 'rst' for reStructuredText
      - 'mrk' for Markdown
      - 'txl' for Textile

    Use examples on templates:

        {# article have a content and markup attributes #}
        {% render_content article %}

        {# article have a body and markup atributes #}
        {% render_content article 'body' %}

        {# we want to display the  summary instead #}
        {% render_content article 'summary' %}

        {# post have a tease and a markup_style attributes #}
        {% render_content post 'tease' 'markup_style' %}

        {# essay have a content and markup_lang attributes #}
        {% render_content essay 'content' 'markup_lang' %}

    """
    return {
        'content': getattr(article, content_attr),
        'markup': getattr(article, markup_attr)
    }