Function open_graph_article 

pub fn open_graph_article(
    page_title: &str,
    description: &str,
    image: &str,
    url: &str,
    author: Option<&str>,
    published_time: Option<&str>,
    modified_time: Option<&str>,
) -> Vec<Element>

Open Graph tags for an article, with the article:* extensions.