There are times when the same tag is used multiple times; we should look into making those elements into arrays in the opengraph dictionary. For an example, see the article:tag on this site. The tags are as follows:

<meta property="article:tag" content="Python">
<meta property="article:tag" content="strings">
<meta property="article:tag" content="tuples">

Currently, we keep the final tag, and not the array of all of them. It would be an improvement to add these to an array if multiple are found. Unless there is a listing of those types that are always arrays that we could use instead.